Common use of Underwriting Agreement Clause in Contracts

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19, 2005, between Principal Commercial Funding, LLC ("Seller"), and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 2005-TOP18 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, Class A-J, Class B, Class C and Class D Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2, 2005, as supplemented by a Prospectus Supplement dated April 19, 2005 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LASALLE LOANS) Mortgage Loan Purchase Agreement (this "Agreement"), dated as of April 19February 15, 20052007, between Principal Commercial Funding, LLC LaSalle Bank National Association (the "Seller"), and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. (the "Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April February 1, 2005 2007, between Purchaser, as depositor, Wells Capmark Finance Inc., as master servicer, X.X. Xxxxxx Company, Inc., as special servicer ("Special Servicer"), Xxxxx Fargo Bank, National Association, as master servicer trustee and custodian (the "Master XxxxicerTrustee"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), ) and LaSalle Bank National Association, as trustee (the "Trustee")paying agent, Wells Fargo Bank, National Association, as paying agent certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans")) to be purchased by Purchaser, the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 HQ11 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, Class A-J, Class B, Class C and Class D Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2, 2005, as supplemented by a Prospectus Supplement dated April 19, 2005 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:.

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR XXXXXXX COMMERCIAL MORTGAGE LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 20, 20052004, between Principal Bear Xxxxxxx Commercial FundingMortgage, LLC Inc. ("Seller"), and Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April November 1, 2005 2004 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar registrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052004-TOP18 TOP16 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-5, Class A-JA-6, Class B, Class C C, Class D, Class E and Class D X-2 Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19October 20, 2005 2004 (the "Underwriting Agreement"), and the Class X, Class EX-1, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 20, 2005 2004 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 11, 20052004, as supplemented by a Prospectus Supplement dated April 19October 20, 2005 2004 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 20, 2005 2004 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 20, 20052004, between Principal Commercial Funding, LLC ("Seller"), and Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April November 1, 2005 2004 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar registrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052004-TOP18 TOP16 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-5, Class A-JA-6, Class B, Class C C, Class D, Class E and Class D X-2 Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19October 20, 2005 2004 (the "Underwriting Agreement"), and the Class X, Class EX-1, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 20, 2005 2004 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 11, 20052004, as supplemented by a Prospectus Supplement dated April 19October 20, 2005 2004 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 20, 2005 2004 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL WELLS LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April xx Xpril 19, 2005, between Principal Commercial FundingWells Fargo Bank, LLC National Association ("Seller"), and Bear Stearns Commercial Comxxxxxal Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 2005-TOP18 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, Class A-J, Class B, Class C and Class D Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2, 2005, as supplemented by a Prospectus Supplement dated April 19, 2005 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19, 2005, between Principal Commercial Funding, LLC Morgan Stanley Mortgage Capital Inc. ("Seller"), and Bear Stearns Commercial Mortgage Commexxxxx Mxxxxxxx Securities Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Trust Inc., Commercial Mortgage PassXxxx-Txxxxxx Xxrough Certificates, Series 2005-TOP18 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, Class A-J, Class B, Class C and Class D Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated Incorporated, (the "Initial XxxxxxxersXxxxxxsers") pursuant tx xx x Xxrxxxxxxxe Xexxxxxxxte Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2, 2005, as supplemented by a Prospectus Supplement dated April 19, 2005 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL XXXXX LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 20, 20052004, between Principal Commercial FundingXxxxx Fargo Bank, LLC National Association ("Seller"), and Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April November 1, 2005 2004 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar registrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052004-TOP18 TOP16 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-5, Class A-JA-6, Class B, Class C C, Class D, Class E and Class D X-2 Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19October 20, 2005 2004 (the "Underwriting Agreement"), and the Class X, Class EX-1, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 20, 2005 2004 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 11, 20052004, as supplemented by a Prospectus Supplement dated April 19October 20, 2005 2004 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 20, 2005 2004 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL AMERICAN MORTGAGE ACCEPTANCE COMPANY LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19December 20, 20052007, between Principal Commercial Funding, LLC American Mortgage Acceptance Company ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April December 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Wachovia Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as trustee (in such capacity, the "Trustee"), custodian, paying agent and certificate xxxxstrar and ABN AMRO Bank N.V.(in such capacity, as fiscal agent (the "Fiscal Paying Agent"), certificate registrar and authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively collectively, the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 HQ13 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19December 20, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (in such capacity, the "Initial XxxxxxxersPurchaser") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial PurchasersPurchaser, dated April 19December 30, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2December 12, 20052007, as supplemented by a Prospectus Supplement dated April 19December 20, 2005 2007 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19December 20, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR STEARNS COMMERCIAL MORTGAGE LOANS) Mortgage Loan Purchase Agreement ("AgreementXxxxxxent"), dated as of April 19, 2005, between Principal Bear Stearns Commercial FundingMortgage, LLC Inc. ("Seller"), and Bear Stearns Commercial Mortgage Commercixx Xxxxgage Securities Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 2005-TOP18 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, Class A-J, Class B, Class C and Class D Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2, 2005, as supplemented by a Prospectus Supplement dated April 19, 2005 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 20, 20052004, between Principal Commercial Funding, LLC Xxxxxx Xxxxxxx Mortgage Capital Inc. ("Seller"), and Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April November 1, 2005 2004 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar registrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052004-TOP18 TOP16 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-5, Class A-JA-6, Class B, Class C C, Class D, Class E and Class D X-2 Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19October 20, 2005 2004 (the "Underwriting Agreement"), and the Class X, Class EX-1, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Inc., Xxxxxx Xxxxxxx & Co. Incorporated Incorporated, Xxxxxxx, Sachs & Co. and Xxxxx Fargo Brokerage Services, LLC (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 20, 2005 2004 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 11, 20052004, as supplemented by a Prospectus Supplement dated April 19October 20, 2005 2004 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 20, 2005 2004 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL NOMURA CREDIT & CAPITAL, INC. LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19December 20, 20052007, between Principal Commercial FundingNomura Credit & Capital, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April December 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Wachovia Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as trustee (in such capacity, the "Trustee"), custodian, paying agent and certificate xxxxstrar and ABN AMRO Bank N.V.(in such capacity, as fiscal agent (the "Fiscal Paying Agent"), certificate registrar and authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively collectively, the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 HQ13 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19December 20, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (in such capacity, the "Initial XxxxxxxersPurchaser") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial PurchasersPurchaser, dated April 19December 20, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2December 12, 20052007, as supplemented by a Prospectus Supplement dated April 19December 20, 2005 2007 (together, the "Prospectus Supplement"), and the Initial Purchasers Purchaser will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19December 20, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL XXXXXX XXXXXXX MORTGAGE CAPITAL HOLDINGS LLC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19December 20, 20052007, between Principal Commercial Funding, Xxxxxx Xxxxxxx Mortgage Capital Holdings LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April December 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Wachovia Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells and Xxxxx Fargo Bank, National Association, as trustee (in such capacity, the "Trustee"), custodian, paying agent and certificate xxxxstrar and ABN AMRO Bank N.V.(in such capacity, as fiscal agent (the "Fiscal Paying Agent"), certificate registrar and authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively collectively, the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 HQ13 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19December 20, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (in such capacity, the "Initial XxxxxxxersPurchaser") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial PurchasersPurchaser, dated April 19December 20, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2December 12, 20052007, as supplemented by a Prospectus Supplement dated April 19December 20, 2005 2007 (together, the "Prospectus Supplement"), and the Initial Purchasers Purchaser will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19December 20, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR XXXXXXX COMMERCIAL MORTGAGE, INC. LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Bear Xxxxxxx Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-AB, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19, 2005, between Principal Commercial Funding, LLC ("Seller")The Issuing Entity will be formed, and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser Certificates will convey the Mortgage Loans to a trust (the "Trust") created be issued, pursuant to a Pooling pooling and Servicing Agreement servicing agreement (the "“Pooling and Servicing Agreement"), to be ”) dated as of April March 1, 2005 between Purchaser2007, as depositorby and among the Depositor, Wells Fargo BankHSBC Bank USA, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "“Trustee"”), Wells Wxxxx Fargo Bank, National AssociationN.A., in the capacities of master servicer (in such capacity, the “Master Servicer”), securities administrator (in such capacity, the “Securities Administrator”), and acknowledged by RWT Holdings, Inc., a Delaware corporation and wholly-owned subsidiary of Redwood Trust, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent seller (the "Fiscal Agent"“Seller”). In exchange for On or about March 30, 2007 (the “Closing Date”), the Seller will assign all of its right, title and interest in the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates pursuant to be known a mortgage loan purchase and sale agreement, dated as Bear Stearns Commercial Mortgage Securities Inc.of March 1, Commercial Mortgage Pass-Txxxxxx Certificates, Series 2005-TOP18 2007 (the "Certificates"“Mortgage Loan Purchase Agreement”), between the Seller, as seller, and the Depositor, as purchaser. The Certificates will be issued pursuant Pursuant to the Pooling and Servicing Agreement, the Mortgage Loans will, in turn, be assigned by the Depositor to the Trustee for the benefit of the Certificateholders, together with all principal and interest collections received with respect to the Mortgage Loans after March 1, 2007 (the “Cut-off Date”). The Trustee will concurrently with such assignment, authenticate and deliver the Certificates to the Depositor, and the Depositor will sell the Publicly-Offered Certificates to the Underwriters. In addition, pursuant to various assignment, assumption and recognition agreements (collectively, the “Assignment Agreements”), (i) the Seller will assign its rights under various underlying mortgage loan purchase and servicing agreements relating to the Mortgage Loans entered into by the Seller (collectively, the “Underlying Purchase and Servicing Agreements”), to the Depositor and (ii) the Depositor will, in turn, assign its rights under the Underlying Purchase and Servicing Agreements to the Trustee for the benefit of the Certificateholders. The Master Servicer will monitor the servicing of the Mortgage Loans by the servicers pursuant to the provisions of the Pooling and Servicing Agreement. 214709 SEMT 2007-1 Underwriting Agreement The Pooling and Servicing Agreement, the Mortgage Loan Purchase Agreement, the Assignment Agreements and this Agreement are sometimes referred to herein collectively as the “Transaction Documents.” Capitalized terms used herein but not defined herein shall have the respective meanings assigned set forth in this Agreement (or by reference to them Section 10 hereof) or, if not defined therein, as set forth in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, Class A-J, Class B, Class C and Class D Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2, 2005, as supplemented by a Prospectus Supplement dated April 19, 2005 (together, the "Prospectus Supplement"), and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:.

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 196, 20052006, between Principal Commercial FundingFunding II, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxxxx agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")xxxxstrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnxxxxxxtxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agxxxxxxx, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInxxxxx Pxxxxxxxrs") pursuant tx x Xxrxxxxxxxe Purchase to a Certificate Xxxxxxse Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL XXXXX LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April July 19, 20052006, between Principal Commercial FundingXxxxx Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April August 1, 2005 2006 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052006-TOP18 TOP23 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April July 19, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April July 19, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April July 19, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April July 19, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT WELLS FARGO BANK, NATIONAL ASSOCIATION (PRINCIPAL LOANS) WELLS LOANS Mortgage Loan Purchase Agreement ("Agreement"), dated as of ax xx April 195, 20052007, between Principal Commercial FundingWells Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Cxxxxxcial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and agent, certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052007-TOP18 TOP26 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderxxxxxxx"), pursuant to an Xxxxxxrxxxxx Xgreementxx Xxxexxxxxxxg Agreement, between Purchaser and the Underwriters, dated April 195, 2005 2007 (the "Underwriting Agreement"), and the Class XX-1, Class X-2, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInitixx Xxxxhasers") pursuant tx pursuanx xx x Xxrxxxxxxxe Xxxxxxxcate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 195, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2September 13, 20052006, as supplemented by a Prospectus Supplement dated April 195, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 195, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19January 20, 20052006, between Principal Commercial Funding, LLC Morgan Stanley Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Inc. Morgan Stanlex Xxxxtxx X Xxc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to sexx xxx Xxxxxxxer agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerXxxxxr Servicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certixxxxxe registrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc., Commercial Mortgage Pass-Txxxxxx CertificatesThrough Cxxxxxxcxxxx, Series 2005Xeries 2006-TOP18 TOP21 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "UnderwrixxxxXxdxxxxxxxrs"), pursuant to an Xxxxxxrxxxxx XgreementUnderwritxxx Xxxeement, between Purchaser and the Underwriters, dated April 19January 20, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "Initial XxxxxxxersXxixxxx Xxrchasers") pursuant tx x Xxrxxxxxxxe to a Certixxxxxx Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19January 20, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 7, 2005, as supplemented by a Prospectus Supplement dated April 19January 20, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19January 20, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR STEARNS COMMERCIAL MORTGAGE LOANS) Mortgage Loan Purchase Agreement Agreemxxx ("AgreementXgreement"), dated as of April 19January 20, 20052006, between Principal Bear Stearns Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Morgan Stanley Cxxxxxx I Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to sexx xxx Xxxxxxxer agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerXxxxxr Servicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certixxxxxe registrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc., Commercial Mortgage Pass-Txxxxxx CertificatesThrough Cxxxxxxcxxxx, Series 2005Xeries 2006-TOP18 TOP21 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "UnderwrixxxxXxdxxxxxxxrs"), pursuant to an Xxxxxxrxxxxx XgreementUnderwritxxx Xxxeement, between Purchaser and the Underwriters, dated April 19January 20, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "Initial XxxxxxxersXxixxxx Xxrchasers") pursuant tx x Xxrxxxxxxxe to a Certixxxxxx Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19January 20, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 7, 2005, as supplemented by a Prospectus Supplement dated April 19January 20, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19January 20, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 18, 20052006, between Principal Commercial FundingFunding II, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April October 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and agent, certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052006-TOP18 TOP24 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxwxxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxent, between Purchaser and the Underwriters, dated April 19October 18, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxax Xxxxxasers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificxxx Xxxchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 18, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2September 13, 20052006, as supplemented by a Prospectus Supplement dated April 19October 18, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 18, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL WELLS LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19Jxxx 09, 20052007, between Principal Commercial FundingWells Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Morgan Stanley Xxxxxal I Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to sell axx Xxxcxxxxx xgrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April July 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMastxx Xxrvicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent agent, certificate xxxxxtrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc., Commercial Mortgage Pass-Txxxxxx CertificatesThrough Certixxxxxxs, Series 2005Xxxxxs 2007-TOP18 TOP27 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxxrxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxxnt, between Purchaser and the Underwriters, dated April July 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class A-MFL, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and II, Class R-III and Class AW34 Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxxl Xxxxxxsers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificaxx Xxxxhase Agreement, between Purchaser and the Initial Purchasers, dated April July 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 22, 20052007, as supplemented by a Prospectus Supplement dated April July 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April July 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL WELLS LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as datxx xx of April 19January 20, 20052006, between Principal Commercial FundingWells Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Morgan Stanxxx Xapital I Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to sexx xxx Xxxxxxxer agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerXxxxxr Servicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certixxxxxe registrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc., Commercial Mortgage Pass-Txxxxxx CertificatesThrough Cxxxxxxcxxxx, Series 2005Xeries 2006-TOP18 TOP21 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "UnderwrixxxxXxdxxxxxxxrs"), pursuant to an Xxxxxxrxxxxx XgreementUnderwritxxx Xxxeement, between Purchaser and the Underwriters, dated April 19January 20, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "Initial XxxxxxxersXxixxxx Xxrchasers") pursuant tx x Xxrxxxxxxxe to a Certixxxxxx Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19January 20, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 7, 2005, as supplemented by a Prospectus Supplement dated April 19January 20, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19January 20, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 196, 20052006, between Principal Commercial FundingFunding II, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certificxxx xegistrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxwxxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxent, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxax Xxxxxasers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificxxx Xxxchase Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April July 19, 20052006, between Principal Commercial Funding, LLC Xxxxxx Xxxxxxx Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April August 1, 2005 2006 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052006-TOP18 TOP23 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April July 19, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April July 19, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April July 19, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April July 19, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR XXXXXXX COMMERCIAL MORTGAGE LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 20, 2005, between Principal Bear Xxxxxxx Commercial FundingMortgage, LLC Inc. ("Seller"), and Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April October 1, 2005 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar registrar, and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 2005-TOP18 TOP20 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4X-0X, Class A-4FLXxxxx X-0X, Class AXxxxx X-JX, Class B, Class C C, Class D and Class D E Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19October 20, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class Q, Class LF, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 20, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March September 2, 2005, as supplemented by a Prospectus Supplement dated April 19October 20, 2005 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 20, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR STEARNS COMMERCIAL MORTGAGE, INC. LOANS) Mortgage Loan Purchase Agreement Agrexxxxx ("Agreement"), dated as of April July 19, 20052007, between Principal Bear Stearns Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Inc. Morgan Stanley Capitxx X Xxc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to sell axx Xxxcxxxxx xgrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April July 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMastxx Xxrvicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent agent, certificate xxxxxtrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc., Commercial Mortgage Pass-Txxxxxx CertificatesThrough Certixxxxxxs, Series 2005Xxxxxs 2007-TOP18 TOP27 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxxrxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxxnt, between Purchaser and the Underwriters, dated April July 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class A-MFL, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and II, Class R-III and Class AW34 Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxxl Xxxxxxsers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificaxx Xxxxhase Agreement, between Purchaser and the Initial Purchasers, dated April July 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 22, 20052007, as supplemented by a Prospectus Supplement dated April July 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April July 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Commercial Funding, LLC Mxxxxx Sxxxxxx Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Wxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Wxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class XX-1, Class X-2, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:: AGREEMENT TO PURCHASE. SELLER AGREES TO SELL, AND PURCHASER AGREES TO PURCHASE, ON A SERVICING RELEASED BASIS, THE MORTGAGE LOANS IDENTIFIED ON THE SCHEDULE (THE "MORTGAGE LOAN SCHEDULE") ANNEXED HERETO AS EXHIBIT 1, AS SUCH SCHEDULE MAY BE AMENDED TO REFLECT THE ACTUAL MORTGAGE LOANS ACCEPTED BY PURCHASER PURSUANT TO THE TERMS HEREOF. THE CUT-OFF DATE WITH RESPECT TO THE MORTGAGE LOANS IS JANUARY 1, 2007. THE MORTGAGE LOANS WILL HAVE AN AGGREGATE PRINCIPAL BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF (I) $321,582,198, PLUS (II) THE 50% PARI PASSU INTEREST OF THE SELLER IN THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN, WHICH SUCH PARI PASSU INTEREST IS REPRESENTED BY THE RELATED MORTGAGE NOTE WITH A CUT-OFF DATE BALANCE OF $23,375,000. SELLER AND PRINCIPAL COMMERCIAL FUNDING II, LLC CO-ORIGINATED THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN, WHICH WILL HAVE AN AGGREGATE BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF $46,750,000. THE SALE OF THE MORTGAGE LOANS SHALL TAKE PLACE ON JANUARY 30, 2007 OR SUCH OTHER DATE AS SHALL BE MUTUALLY ACCEPTABLE TO THE PARTIES HERETO (THE "CLOSING DATE"). THE PURCHASE PRICE TO BE PAID BY PURCHASER FOR THE MORTGAGE LOANS SHALL EQUAL THE AMOUNT SET FORTH AS SUCH PURCHASE PRICE ON EXHIBIT 3 HERETO. THE PURCHASE PRICE SHALL BE PAID TO SELLER BY WIRE TRANSFER IN IMMEDIATELY AVAILABLE FUNDS ON THE CLOSING DATE. NOTWITHSTANDING ANYTHING TO THE CONTRARY CONTAINED HEREIN, WITH RESPECT TO THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN, REFERENCES TO A MORTGAGE NOTE HEREIN SHALL MEAN THE MORTGAGE NOTE RELATED TO THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN. ON THE CLOSING DATE, PURCHASER WILL ASSIGN TO THE TRUSTEE PURSUANT TO THE POOLING AND SERVICING AGREEMENT ALL OF ITS RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND ITS RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF), AND THE TRUSTEE SHALL SUCCEED TO SUCH RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND PURCHASER'S RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF). CONVEYANCE OF MORTGAGE LOANS. EFFECTIVE AS OF THE CLOSING DATE, SUBJECT ONLY TO RECEIPT OF THE CONSIDERATION REFERRED TO IN SECTION 1 HEREOF AND THE SATISFACTION OF THE CONDITIONS SPECIFIED IN SECTIONS 6 AND 7 HEREOF, SELLER DOES HEREBY TRANSFER, ASSIGN, SET OVER AND OTHERWISE CONVEY TO PURCHASER, WITHOUT RECOURSE, EXCEPT AS SPECIFICALLY PROVIDED HEREIN ALL THE RIGHT, TITLE AND INTEREST OF SELLER, WITH THE UNDERSTANDING THAT A SERVICING RIGHTS PURCHASE AND SALE AGREEMENT, DATED JANUARY 1, 2007, WILL BE EXECUTED BY SELLER AND THE MASTER SERVICER, IN AND TO THE MORTGAGE LOANS IDENTIFIED ON THE MORTGAGE LOAN SCHEDULE AS OF THE CLOSING DATE. THE MORTGAGE LOAN SCHEDULE, AS IT MAY BE AMENDED FROM TIME TO TIME ON OR PRIOR TO THE CLOSING DATE, SHALL CONFORM TO THE REQUIREMENTS OF THIS AGREEMENT AND THE POOLING AND SERVICING

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL XXXXX LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Commercial FundingXxxxx Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-AB, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL WELLS LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated xxted as of April 196, 20052006, between Principal Commercial FundingWells Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Commxxxxxl Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxxxx agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")xxxxstrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnxxxxxxtxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agxxxxxxx, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInxxxxx Pxxxxxxxrs") pursuant tx x Xxrxxxxxxxe Purchase to a Certificate Xxxxxxse Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MORGAN STANLEY MORTGAGE CAPITAL HOLDINGS LLC LOANS) Mortgage Loan Purchase Agreement Puxxxxxx Xxxxxxxnt ("Agreement"), dated as of April July 19, 20052007, between Principal Commercial Funding, Morgan Stanley Mortgage Capital Holdings LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Morgan Stxxxxx Cxxxxxx I Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to sell axx Xxxcxxxxx xgrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April July 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMastxx Xxrvicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent agent, certificate xxxxxtrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc., Commercial Mortgage Pass-Txxxxxx CertificatesThrough Certixxxxxxs, Series 2005Xxxxxs 2007-TOP18 TOP27 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxxrxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxxnt, between Purchaser and the Underwriters, dated April July 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class A-MFL, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and II, Class R-III and Class AW34 Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxxl Xxxxxxsers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificaxx Xxxxhase Agreement, between Purchaser and the Initial Purchasers, dated April July 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 22, 20052007, as supplemented by a Prospectus Supplement dated April July 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April July 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 18, 20052006, between Principal Commercial Funding, LLC Morgan Stanley Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Comxxxxxxl Xxxxxxge Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April October 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and agent, certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052006-TOP18 TOP24 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxwxxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxent, between Purchaser and the Underwriters, dated April 19October 18, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxax Xxxxxasers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificxxx Xxxchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 18, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2September 13, 20052006, as supplemented by a Prospectus Supplement dated April 19October 18, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 18, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL WELLS LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of xx xx April 196, 20052006, between Principal Commercial FundingWells Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Cxxxxxcial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certificxxx xegistrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxwxxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxent, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxax Xxxxxasers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificxxx Xxxchase Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR XXXXXXX COMMERCIAL MORTGAGE LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19January 20, 20052006, between Principal Bear Xxxxxxx Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2006 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")registrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052006-TOP18 TOP21 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19January 20, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19January 20, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 7, 2005, as supplemented by a Prospectus Supplement dated April 19January 20, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19January 20, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR STEARNS COMMERCIAL MORTGAGE LOANS) Mortgage Loan Purchase Agreement Xxxxxxxnt ("Agreement"), dated as of April 196, 20052006, between Principal Bear Stearns Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Commerciax Xxxxxage Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxxxx agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent agent, certificate rexxxxxar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 MORTGAGE LOAN PURCHASE AGREEMENT Subject to the terms and conditions set forth and incorporated by reference herein, the Depositor hereby agrees to issue and sell to _______________________________________, (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement (collectively, the "Agreement"), dated as of April 19, 2005, between Principal Commercial Funding, LLC ("SellerUnderwriters"), and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees the Underwriters hereby agree to purchase certain mortgage loans listed from the Depositor, on Exhibit 1 hereto or about ______________ the Underwritten Certificates at the purchase price and on the terms set forth below; provided, however, that the obligations of the Underwriters are subject to: (i) receipt by the Depositor of (a) an "[ ]" rating by ____________________________ and an "[ ]" rating by ___________________________; (the "Mortgage LoansRating Agencies") as described herein. Purchaser will convey with respect to the Mortgage Loans Underwritten Certificates; (ii) receipt of a Prospectus Supplement in form and substance satisfactory to a trust the Underwriters; and (iii) the "Trust") created pursuant to a Pooling and Servicing Sales Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1__________________, 2005 by and between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Fargo Bank, National Association, as paying agent Depositor and certificate xxxxstrar ___ and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue Agreement (as defined below) each being in form and substance satisfactory to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 2005-TOP18 (the "Certificates")Underwriters. The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, Class A-J, Class B, Class C and Class D Certificates a Trust Agreement dated as of __________________ 199[ ] (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19, 2005 (the "Underwriting Trust Agreement"), by and among the Class XDepositor, Class E________________________, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates as Master Servicer (the "Private CertificatesMaster Servicer") will be sold by Purchaser to Bear), Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated _________________, as Trustee (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19, 2005 (the "Certificate Purchase AgreementTrustee"). The Underwriters Certificates will offer represent in the Public Certificates for sale publicly pursuant to a Prospectus dated March 2, 2005, as supplemented by a Prospectus Supplement dated April 19, 2005 aggregate the entire beneficial ownership interest in the assets of the Trust created under the Trust Agreement (together, the "Prospectus SupplementTrust"), and the Initial Purchasers which will offer the Private Certificates for sale in transactions exempt from the registration requirements consist primarily of the Securities Act [ ] pool[s] of 1933 pursuant conventional, one- to a Private Placement Memorandum dated April 19four-family, 2005 fully amortizing, mortgage loans (the "MemorandumMortgage Loans")) with original terms to stated maturity of not more than [ ] years which have the characteristics described in the Prospectus Supplement. In consideration The Depositor will make available on the Closing Date for sale, transfer and assignment to the Trust, Mortgage Loans having the characteristics described in the Prospectus Supplement; PROVIDED, HOWEVER, that there may be immaterial variances from the description of the mutual agreements contained hereinMortgage Loans in the Prospectus Supplement and the actual Mortgage Loans delivered on the Closing Date. Upon delivery of the Mortgage Loans to the Depositor, Seller and Purchaser hereby agree as follows:the Depositor will deliver such Mortgage Loans to the Trust. 2.

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR STEARNS COMMERCIAL MORTGAGE, INC. LOANS) Mortgage Loan Purchase Xxxxxxse Agreement ("Agreement"), dated as of April 19October 18, 20052006, between Principal Bear Stearns Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Commerciax Xxxxxage Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxler agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April October 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent agent, certificate rexxxxxar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP24 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Underwrixxxx"), pursuant to an Xxxxxxrxxxxx Xgreement, between Purchaser and the Underwriters, dated April 19October 18, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial Xxxxxxxers") pursuant tx x Xxrxxxxxxxe Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 18, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2September 13, 20052006, as supplemented by a Prospectus Supplement dated April 19October 18, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 18, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:: AGREEMENT TO PURCHASE. SELLER AGREES TO SELL, AND PURCHASER AGREES TO PURCHASE, ON A SERVICING RELEASED BASIS, THE MORTGAGE LOANS IDENTIFIED ON THE SCHEDULE (THE "MORTGAGE LOAN SCHEDULE") ANNEXED HERETO AS EXHIBIT 1, AS SUCH SCHEDULE MAY BE AMENDED TO REFLECT THE ACTUAL MORTGAGE LOANS ACCEPTED BY PURCHASER PURSUANT TO THE TERMS HEREOF. THE CUT-OFF DATE WITH RESPECT TO THE MORTGAGE LOANS IS OCTOBER 1, 2006. THE MORTGAGE LOANS WILL HAVE AN AGGREGATE PRINCIPAL BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF $1,534,723,955. THE SALE OF THE MORTGAGE LOANS SHALL TAKE PLACE ON OCTOBER 31, 2006 OR SUCH OTHER DATE AS SHALL BE MUTUALLY ACCEPTABLE TO THE PARTIES HERETO (THE "CLOSING DATE"). THE PURCHASE PRICE TO BE PAID BY PURCHASER FOR THE MORTGAGE LOANS SHALL EQUAL THE AMOUNT SET FORTH AS SUCH PURCHASE PRICE ON EXHIBIT 3 HERETO. THE PURCHASE PRICE SHALL BE PAID TO SELLER BY WIRE TRANSFER IN IMMEDIATELY AVAILABLE FUNDS ON THE CLOSING DATE. ON THE CLOSING DATE, PURCHASER WILL ASSIGN TO THE TRUSTEE PURSUANT TO THE POOLING AND SERVICING AGREEMENT ALL OF ITS RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND ITS RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF), AND THE TRUSTEE SHALL SUCCEED TO SUCH RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND PURCHASER'S RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF). CONVEYANCE OF MORTGAGE LOANS. EFFECTIVE AS OF THE CLOSING DATE, SUBJECT ONLY TO RECEIPT OF THE CONSIDERATION REFERRED TO IN SECTION 1 HEREOF AND THE SATISFACTION OF THE CONDITIONS SPECIFIED IN SECTIONS 6 AND 7 HEREOF, SELLER DOES HEREBY TRANSFER, ASSIGN, SET OVER AND OTHERWISE CONVEY TO PURCHASER, WITHOUT RECOURSE, EXCEPT AS SPECIFICALLY PROVIDED HEREIN ALL THE RIGHT, TITLE AND INTEREST OF SELLER, WITH THE UNDERSTANDING THAT A SERVICING RIGHTS PURCHASE AND SALE AGREEMENT, DATED OCTOBER 1, 2006, WILL BE EXECUTED BY SELLER AND THE MASTER SERVICER, IN AND TO THE MORTGAGE LOANS IDENTIFIED ON THE MORTGAGE LOAN SCHEDULE AS OF THE CLOSING DATE. THE MORTGAGE LOAN SCHEDULE, AS IT MAY BE AMENDED FROM TIME TO TIME ON OR PRIOR TO THE CLOSING DATE, SHALL CONFORM TO THE REQUIREMENTS OF THIS AGREEMENT AND THE POOLING AND SERVICING AGREEMENT. IN CONNECTION WITH SUCH TRANSFER AND ASSIGNMENT, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE, ON BEHALF OF PURCHASER, ON OR PRIOR TO THE CLOSING DATE, THE MORTGAGE NOTE (AS DESCRIBED IN CLAUSE 2.2.1 HEREOF) FOR EACH MORTGAGE LOAN AND ON OR PRIOR TO THE FIFTH BUSINESS DAY AFTER THE CLOSING DATE, FIVE LIMITED POWERS OF ATTORNEY SUBSTANTIALLY IN THE FORM ATTACHED HERETO AS EXHIBIT 5 IN FAVOR OF THE TRUSTEE AND THE SPECIAL SERVICER TO EMPOWER THE TRUSTEE AND, IN THE EVENT OF THE FAILURE OR INCAPACITY OF THE TRUSTEE, THE SPECIAL SERVICER, TO SUBMIT FOR RECORDING, AT THE EXPENSE OF SELLER, ANY MORTGAGE LOAN DOCUMENTS REQUIRED TO BE RECORDED AS DESCRIBED IN THE POOLING AND SERVICING AGREEMENT AND ANY INTERVENING ASSIGNMENTS WITH EVIDENCE OF RECORDING THEREON THAT ARE REQUIRED TO BE INCLUDED IN THE MORTGAGE FILES (SO LONG AS ORIGINAL COUNTERPARTS HAVE PREVIOUSLY BEEN DELIVERED TO THE TRUSTEE). SELLER AGREES TO REASONABLY COOPERATE WITH THE TRUSTEE AND THE SPECIAL SERVICER IN CONNECTION WITH ANY ADDITIONAL POWERS OF ATTORNEY OR REVISIONS THERETO THAT ARE REQUESTED BY SUCH PARTIES FOR PURPOSES OF SUCH RECORDATION. THE PARTIES HERETO AGREE THAT NO SUCH POWER OF ATTORNEY SHALL BE USED WITH RESPECT TO ANY MORTGAGE LOAN BY OR UNDER AUTHORIZATION BY ANY PARTY HERETO EXCEPT TO THE EXTENT THAT THE ABSENCE OF A DOCUMENT DESCRIBED IN THE SECOND PRECEDING SENTENCE WITH RESPECT TO SUCH MORTGAGE LOAN REMAINS UNREMEDIED AS OF THE EARLIER OF (I) THE DATE THAT IS 180 DAYS FOLLOWING THE DELIVERY OF NOTICE OF SUCH ABSENCE TO SELLER, BUT IN NO EVENT EARLIER THAN 18 MONTHS FROM THE CLOSING DATE, AND (II) THE DATE (IF ANY) ON WHICH SUCH MORTGAGE LOAN BECOMES A SPECIALLY SERVICED MORTGAGE LOAN. THE TRUSTEE SHALL SUBMIT SUCH DOCUMENTS, AT SELLER'S EXPENSE, AFTER THE PERIODS SET FORTH ABOVE, PROVIDED, HOWEVER, THE TRUSTEE SHALL NOT SUBMIT SUCH ASSIGNMENTS FOR RECORDING IF SELLER PRODUCES EVIDENCE THAT IT HAS SENT ANY SUCH ASSIGNMENT FOR RECORDING AND CERTIFIES THAT SELLER IS AWAITING ITS RETURN FROM THE APPLICABLE RECORDING OFFICE. IN ADDITION, NOT LATER THAN THE 30TH DAY FOLLOWING THE CLOSING DATE, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE EACH OF THE REMAINING DOCUMENTS OR INSTRUMENTS SPECIFIED IN SECTION 2.2 HEREOF (WITH SUCH EXCEPTIONS AS ARE PERMITTED BY THIS SECTION 2) WITH RESPECT TO EACH MORTGAGE LOAN (EACH, A "MORTGAGE FILE"). (SELLER ACKNOWLEDGES THAT THE TERM "WITHOUT RECOURSE" DOES NOT MODIFY THE DUTIES OF SELLER UNDER SECTION 5 HEREOF.) ALL MORTGAGE FILES, OR PORTIONS THEREOF, DELIVERED PRIOR TO THE CLOSING DATE ARE TO BE HELD BY OR ON BEHALF OF THE TRUSTEE IN ESCROW ON BEHALF OF SELLER AT ALL TIMES PRIOR TO THE CLOSING DATE. THE MORTGAGE FILES SHALL BE RELEASED FROM ESCROW UPON CLOSING OF THE SALE OF THE MORTGAGE LOANS AND PAYMENTS OF THE PURCHASE PRICE THEREFOR AS CONTEMPLATED HEREBY. THE MORTGAGE FILE FOR EACH MORTGAGE LOAN SHALL CONTAIN THE FOLLOWING DOCUMENTS: THE ORIGINAL MORTGAGE NOTE BEARING ALL INTERVENING ENDORSEMENTS, ENDORSED "PAY TO THE ORDER OF LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24, WITHOUT RECOURSE, REPRESENTATION OR WARRANTY" OR IF THE ORIGINAL MORTGAGE NOTE IS NOT INCLUDED THEREIN, THEN A LOST NOTE AFFIDAVIT, WITH A COPY OF THE MORTGAGE NOTE ATTACHED THERETO; THE ORIGINAL MORTGAGE, WITH EVIDENCE OF RECORDING THEREON, AND, IF THE MORTGAGE WAS EXECUTED PURSUANT TO A POWER OF ATTORNEY, A CERTIFIED TRUE COPY OF THE POWER OF ATTORNEY CERTIFIED BY THE PUBLIC RECORDER'S OFFICE, WITH EVIDENCE OF RECORDING THEREON (IF RECORDING IS CUSTOMARY IN THE JURISDICTION IN WHICH SUCH POWER OF ATTORNEY WAS EXECUTED), OR CERTIFIED BY A TITLE INSURANCE COMPANY OR ESCROW COMPANY TO BE A TRUE COPY THEREOF; PROVIDED THAT IF SUCH ORIGINAL MORTGAGE CANNOT BE DELIVERED WITH EVIDENCE OF RECORDING THEREON ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE BECAUSE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE WHERE SUCH ORIGINAL MORTGAGE HAS BEEN DELIVERED FOR RECORDATION OR BECAUSE SUCH ORIGINAL MORTGAGE HAS BEEN LOST, SELLER SHALL DELIVER OR CAUSE TO BE DELIVERED TO THE TRUSTEE A TRUE AND CORRECT COPY OF SUCH MORTGAGE, TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE (AS DEFINED BELOW) OF SELLER STATING THAT SUCH ORIGINAL MORTGAGE HAS BEEN SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL MORTGAGE THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH MORTGAGE IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED MORTGAGE; THE ORIGINALS OF ALL AGREEMENTS MODIFYING A MONEY TERM OR OTHER MATERIAL MODIFICATION, CONSOLIDATION AND EXTENSION AGREEMENTS, IF ANY, WITH EVIDENCE OF RECORDING THEREON, OR IF ANY SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DELIVERED TO THE APPROPRIATE RECORDING OFFICE FOR RECORDATION AND EITHER HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE WITH EVIDENCE OF RECORDATION THEREON OR HAS BEEN LOST AFTER RECORDATION, A TRUE COPY OF SUCH MODIFICATION, CONSOLIDATION OR EXTENSION CERTIFIED BY SELLER TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DISPATCHED OR SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH DOCUMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT, AND THE ORIGINALS OF ALL ASSUMPTION AGREEMENTS, IF ANY; AN ORIGINAL ASSIGNMENT OF MORTGAGE FOR EACH MORTGAGE LOAN, IN FORM AND SUBSTANCE ACCEPTABLE FOR RECORDING, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24," PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MORTGAGE ELECTRONIC REGISTRATION SYSTEMS, INC. ("MERS") OR ITS DESIGNEE, NO SUCH ASSIGNMENTS WILL BE REQUIRED TO BE SUBMITTED FOR RECORDING OR FILING AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; ORIGINALS OF ALL INTERVENING ASSIGNMENTS OF MORTGAGE (EXCEPT WITH RESPECT TO ANY MORTGAGE THAT HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEES), IF ANY, WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ORIGINAL ASSIGNMENTS OF MORTGAGE HAVE BEEN DELIVERED TO THE APPROPRIATE RECORDER'S OFFICE FOR RECORDATION, CERTIFIED TRUE COPIES OF SUCH ASSIGNMENTS OF MORTGAGE CERTIFIED BY SELLER, OR IN THE CASE OF AN ORIGINAL BLANKET INTERVENING ASSIGNMENT OF MORTGAGE RETAINED BY SELLER, A COPY THEREOF CERTIFIED BY SELLER OR, IF ANY ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE RECORDING OFFICE OR HAS BEEN LOST, A TRUE AND CORRECT COPY THEREOF, TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS BEEN SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH ASSIGNMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED INTERVENING ASSIGNMENT OF MORTGAGE; IF THE RELATED ASSIGNMENT OF LEASES IS SEPARATE FROM THE MORTGAGE, THE ORIGINAL OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT OF LEASES CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT OF LEASES SUBMITTED FOR RECORDING, TOGETHER WITH (I) AN ORIGINAL OF EACH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON AND SHOWING A COMPLETE RECORDED CHAIN OF ASSIGNMENT FROM THE NAMED ASSIGNEE TO THE HOLDER OF RECORD, AND IF ANY SUCH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT SUBMITTED FOR RECORDING, AND (II) AN ORIGINAL ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES, IN RECORDABLE FORM, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24," WHICH ASSIGNMENT MAY BE EFFECTED IN THE RELATED ASSIGNMENT OF MORTGAGE, PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEE, NO ASSIGNMENT OF ASSIGNMENT OF LEASES IN FAVOR OF THE TRUSTEE WILL BE REQUIRED TO BE RECORDED OR DELIVERED AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; THE ORIGINAL OF EACH GUARANTY, IF ANY, CONSTITUTING ADDITIONAL SECURITY FOR THE REPAYMENT OF SUCH MORTGAGE LOAN; THE ORIGINAL TITLE INSURANCE POLICY, OR IN THE EVENT SUCH ORIGINAL TITLE INSURANCE POLICY HAS NOT BEEN ISSUED, AN ORIGINAL BINDER OR ACTUAL TITLE COMMITMENT OR A COPY THEREOF CERTIFIED BY THE TITLE COMPANY WITH THE ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE OR A PRELIMINARY TITLE REPORT BINDING ON THE TITLE COMPANY WITH AN ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE;

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April July 19, 20052006, between Principal Commercial FundingFunding II, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April August 1, 2005 2006 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052006-TOP18 TOP23 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April July 19, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April July 19, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April July 19, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April July 19, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR SXXXXXX COMMERCIAL MORTGAGE, INC. LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Bear Sxxxxxx Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Wxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Wxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-AB, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:: AGREEMENT TO PURCHASE. SELLER AGREES TO SELL, AND PURCHASER AGREES TO PURCHASE, ON A SERVICING RELEASED BASIS, THE MORTGAGE LOANS IDENTIFIED ON THE SCHEDULE (THE "MORTGAGE LOAN SCHEDULE") ANNEXED HERETO AS EXHIBIT 1, AS SUCH SCHEDULE MAY BE AMENDED TO REFLECT THE ACTUAL MORTGAGE LOANS ACCEPTED BY PURCHASER PURSUANT TO THE TERMS HEREOF. THE CUT-OFF DATE WITH RESPECT TO THE MORTGAGE LOANS IS JANUARY 1, 2007. THE MORTGAGE LOANS WILL HAVE AN AGGREGATE PRINCIPAL BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF $387,647,782. THE SALE OF THE MORTGAGE LOANS SHALL TAKE PLACE ON JANUARY 30, 2007 OR SUCH OTHER DATE AS SHALL BE MUTUALLY ACCEPTABLE TO THE PARTIES HERETO (THE "CLOSING DATE"). THE PURCHASE PRICE TO BE PAID BY PURCHASER FOR THE MORTGAGE LOANS SHALL EQUAL THE AMOUNT SET FORTH AS SUCH PURCHASE PRICE ON EXHIBIT 3 HERETO. THE PURCHASE PRICE SHALL BE PAID TO SELLER BY WIRE TRANSFER IN IMMEDIATELY AVAILABLE FUNDS ON THE CLOSING DATE. ON THE CLOSING DATE, PURCHASER WILL ASSIGN TO THE TRUSTEE PURSUANT TO THE POOLING AND SERVICING AGREEMENT ALL OF ITS RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND ITS RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF), AND THE TRUSTEE SHALL SUCCEED TO SUCH RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND PURCHASER'S RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF). CONVEYANCE OF MORTGAGE LOANS. EFFECTIVE AS OF THE CLOSING DATE, SUBJECT ONLY TO RECEIPT OF THE CONSIDERATION REFERRED TO IN SECTION 1 HEREOF AND THE SATISFACTION OF THE CONDITIONS SPECIFIED IN SECTIONS 6 AND 7 HEREOF, SELLER DOES HEREBY TRANSFER, ASSIGN, SET OVER AND OTHERWISE CONVEY TO PURCHASER, WITHOUT RECOURSE, EXCEPT AS SPECIFICALLY PROVIDED HEREIN ALL THE RIGHT, TITLE AND INTEREST OF SELLER, WITH THE UNDERSTANDING THAT A SERVICING RIGHTS PURCHASE AND SALE AGREEMENT, DATED JANUARY 1, 2007, WILL BE EXECUTED BY SELLER AND THE MASTER SERVICER, IN AND TO THE MORTGAGE LOANS IDENTIFIED ON THE MORTGAGE LOAN SCHEDULE AS OF THE CLOSING DATE. THE MORTGAGE LOAN SCHEDULE, AS IT MAY BE AMENDED FROM TIME TO TIME ON OR PRIOR TO THE CLOSING DATE, SHALL CONFORM TO THE REQUIREMENTS OF THIS AGREEMENT AND THE POOLING AND SERVICING AGREEMENT. IN CONNECTION WITH SUCH TRANSFER AND ASSIGNMENT, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE, ON BEHALF OF PURCHASER, ON OR PRIOR TO THE CLOSING DATE, THE MORTGAGE NOTE (AS DESCRIBED IN CLAUSE 2.2.1 HEREOF) FOR EACH MORTGAGE LOAN AND ON OR PRIOR TO THE FIFTH BUSINESS DAY AFTER THE CLOSING DATE, FIVE LIMITED POWERS OF ATTORNEY SUBSTANTIALLY IN THE FORM ATTACHED HERETO AS EXHIBIT 5 IN FAVOR OF THE TRUSTEE AND THE SPECIAL SERVICER TO EMPOWER THE TRUSTEE AND, IN THE EVENT OF THE FAILURE OR INCAPACITY OF THE TRUSTEE, THE SPECIAL SERVICER, TO SUBMIT FOR RECORDING, AT THE EXPENSE OF SELLER, ANY MORTGAGE LOAN DOCUMENTS REQUIRED TO BE RECORDED AS DESCRIBED IN THE POOLING AND SERVICING AGREEMENT AND ANY INTERVENING ASSIGNMENTS WITH EVIDENCE OF RECORDING THEREON THAT ARE REQUIRED TO BE INCLUDED IN THE MORTGAGE FILES (SO LONG AS ORIGINAL COUNTERPARTS HAVE PREVIOUSLY BEEN DELIVERED TO THE TRUSTEE). SELLER AGREES TO REASONABLY COOPERATE WITH THE TRUSTEE AND THE SPECIAL SERVICER IN CONNECTION WITH ANY ADDITIONAL POWERS OF ATTORNEY OR REVISIONS THERETO THAT ARE REQUESTED BY SUCH PARTIES FOR PURPOSES OF SUCH RECORDATION. THE PARTIES HERETO AGREE THAT NO SUCH POWER OF ATTORNEY SHALL BE USED WITH RESPECT TO ANY MORTGAGE LOAN BY OR UNDER AUTHORIZATION BY ANY PARTY HERETO EXCEPT TO THE EXTENT THAT THE ABSENCE OF A DOCUMENT DESCRIBED IN THE SECOND PRECEDING SENTENCE WITH RESPECT TO SUCH MORTGAGE LOAN REMAINS UNREMEDIED AS OF THE EARLIER OF (I) THE DATE THAT IS 180 DAYS FOLLOWING THE DELIVERY OF NOTICE OF SUCH ABSENCE TO SELLER, BUT IN NO EVENT EARLIER THAN 18 MONTHS FROM THE CLOSING DATE, AND (II) THE DATE (IF ANY) ON WHICH SUCH MORTGAGE LOAN BECOMES A SPECIALLY SERVICED MORTGAGE LOAN. THE TRUSTEE SHALL SUBMIT SUCH DOCUMENTS, AT SELLER'S EXPENSE, AFTER THE PERIODS SET FORTH ABOVE, PROVIDED, HOWEVER, THE TRUSTEE SHALL NOT SUBMIT SUCH ASSIGNMENTS FOR RECORDING IF SELLER PRODUCES EVIDENCE THAT IT HAS SENT ANY SUCH ASSIGNMENT FOR RECORDING AND CERTIFIES THAT SELLER IS AWAITING ITS RETURN FROM THE APPLICABLE RECORDING OFFICE. IN ADDITION, NOT LATER THAN THE 30TH DAY FOLLOWING THE CLOSING DATE, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE EACH OF THE REMAINING DOCUMENTS OR INSTRUMENTS SPECIFIED IN SECTION 2.2 HEREOF (WITH SUCH EXCEPTIONS AS ARE PERMITTED BY THIS SECTION 2) WITH RESPECT TO EACH MORTGAGE LOAN (EACH, A "MORTGAGE FILE"). (SELLER ACKNOWLEDGES THAT THE TERM "WITHOUT RECOURSE" DOES NOT MODIFY THE DUTIES OF SELLER UNDER SECTION 5 HEREOF.) ALL MORTGAGE FILES, OR PORTIONS THEREOF, DELIVERED PRIOR TO THE CLOSING DATE ARE TO BE HELD BY OR ON BEHALF OF THE TRUSTEE IN ESCROW ON BEHALF OF SELLER AT ALL TIMES PRIOR TO THE CLOSING DATE. THE MORTGAGE FILES SHALL BE RELEASED FROM ESCROW UPON CLOSING OF THE SALE OF THE MORTGAGE LOANS AND PAYMENTS OF THE PURCHASE PRICE THEREFOR AS CONTEMPLATED HEREBY. THE MORTGAGE FILE FOR EACH MORTGAGE LOAN SHALL CONTAIN THE FOLLOWING DOCUMENTS: THE ORIGINAL MORTGAGE NOTE BEARING ALL INTERVENING ENDORSEMENTS, ENDORSED "PAY TO THE ORDER OF LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR MXXXXX SXXXXXX CAPITAL I INC., COMMERCIAL MORTGAGE PASS-THROUGH CERTIFICATES, SERIES 2007-TOP25, WITHOUT RECOURSE, REPRESENTATION OR WARRANTY" OR IF THE ORIGINAL MORTGAGE NOTE IS NOT INCLUDED THEREIN, THEN A LOST NOTE AFFIDAVIT, WITH A COPY OF THE MORTGAGE NOTE ATTACHED THERETO; THE ORIGINAL MORTGAGE, WITH EVIDENCE OF RECORDING THEREON, AND, IF THE MORTGAGE WAS EXECUTED PURSUANT TO A POWER OF ATTORNEY, THE ORIGINALS OF ALL AGREEMENTS MODIFYING A MONEY TERM OR OTHER MATERIAL MODIFICATION, CONSOLIDATION AND EXTENSION AGREEMENTS, IF ANY, WITH EVIDENCE OF RECORDING THEREON, OR IF ANY SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DELIVERED TO THE APPROPRIATE RECORDING OFFICE FOR RECORDATION AND EITHER HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE WITH EVIDENCE OF RECORDATION THEREON OR HAS BEEN LOST AFTER RECORDATION, A TRUE COPY OF SUCH MODIFICATION, CONSOLIDATION OR EXTENSION CERTIFIED BY SELLER TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DISPATCHED OR SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH DOCUMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT, AND THE ORIGINALS OF ALL ASSUMPTION AGREEMENTS, IF ANY; AN ORIGINAL ASSIGNMENT OF MORTGAGE FOR EACH MORTGAGE LOAN, IN FORM AND SUBSTANCE ACCEPTABLE FOR RECORDING, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR MXXXXX SXXXXXX CAPITAL I INC., COMMERCIAL MORTGAGE PASS-THROUGH CERTIFICATES, SERIES 2007-TOP25," PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MORTGAGE ELECTRONIC REGISTRATION SYSTEMS, INC. ("MERS") OR ITS DESIGNEE, NO SUCH ASSIGNMENTS WILL BE REQUIRED TO BE SUBMITTED FOR RECORDING OR FILING AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; ORIGINALS OF ALL INTERVENING ASSIGNMENTS OF MORTGAGE (EXCEPT WITH RESPECT TO ANY MORTGAGE THAT HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEES), IF ANY, WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ORIGINAL ASSIGNMENTS OF MORTGAGE HAVE BEEN DELIVERED TO THE APPROPRIATE RECORDER'S OFFICE FOR RECORDATION, CERTIFIED TRUE COPIES OF SUCH ASSIGNMENTS OF MORTGAGE CERTIFIED BY SELLER, OR IN THE CASE OF AN ORIGINAL BLANKET INTERVENING ASSIGNMENT OF MORTGAGE RETAINED BY SELLER, A COPY THEREOF CERTIFIED BY SELLER OR, IF ANY ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE RECORDING OFFICE OR HAS BEEN LOST, A TRUE AND CORRECT COPY THEREOF, TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS BEEN SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH ASSIGNMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED INTERVENING ASSIGNMENT OF MORTGAGE; IF THE RELATED ASSIGNMENT OF LEASES IS SEPARATE FROM THE MORTGAGE, THE ORIGINAL OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT OF LEASES CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT OF LEASES SUBMITTED FOR RECORDING, TOGETHER WITH (I) AN ORIGINAL OF EACH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON AND SHOWING A COMPLETE RECORDED CHAIN OF ASSIGNMENT FROM THE NAMED ASSIGNEE TO THE HOLDER OF RECORD, AND IF ANY SUCH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT SUBMITTED FOR RECORDING, AND (II) AN ORIGINAL ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES, IN RECORDABLE FORM, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR MXXXXX SXXXXXX CAPITAL I INC., COMMERCIAL MORTGAGE PASS-THROUGH CERTIFICATES, SERIES 2007-TOP25," WHICH ASSIGNMENT MAY BE EFFECTED IN THE RELATED ASSIGNMENT OF MORTGAGE, PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEE, NO ASSIGNMENT OF ASSIGNMENT OF LEASES IN FAVOR OF THE TRUSTEE WILL BE REQUIRED TO BE RECORDED OR DELIVERED AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; THE ORIGINAL OF EACH GUARANTY, IF ANY, CONSTITUTING ADDITIONAL SECURITY FOR THE REPAYMENT OF SUCH MORTGAGE LOAN; THE ORIGINAL TITLE INSURANCE POLICY, OR IN THE EVENT SUCH ORIGINAL TITLE INSURANCE POLICY HAS NOT BEEN ISSUED, AN ORIGINAL BINDER OR ACTUAL TITLE COMMITMENT OR A COPY THEREOF CERTIFIED BY THE TITLE COMPANY WITH THE ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE OR A PRELIMINARY TITLE REPORT BINDING ON THE TITLE COMPANY WITH AN ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE;

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Commercial Funding, LLC Xxxxxx Xxxxxxx Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class XX-1, Class X-2, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR XXXXXXX COMMERCIAL MORTGAGE LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19January 20, 20052006, between Principal Bear Xxxxxxx Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2006 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")registrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052006-TOP18 TOP21 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19January 20, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19January 20, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 7, 2005, as supplemented by a Prospectus Supplement dated April 19January 20, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19January 20, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL BEAR XXXXXXX COMMERCIAL MORTGAGE, INC. LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April July 19, 20052006, between Principal Bear Xxxxxxx Commercial FundingMortgage, LLC Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April August 1, 2005 2006 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052006-TOP18 TOP23 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April July 19, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April July 19, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April July 19, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April July 19, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 195, 20052007, between Principal Commercial Funding, LLC Morgan Stanley Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Comxxxxxxl Xxxxxxge Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2007 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and agent, certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052007-TOP18 TOP26 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderxxxxxxx"), pursuant to an Xxxxxxrxxxxx Xgreementxx Xxxexxxxxxxg Agreement, between Purchaser and the Underwriters, dated April 195, 2005 2007 (the "Underwriting Agreement"), and the Class XX-1, Class X-2, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInitixx Xxxxhasers") pursuant tx pursuanx xx x Xxrxxxxxxxe Xxxxxxxcate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 195, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2September 13, 20052006, as supplemented by a Prospectus Supplement dated April 195, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 195, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Commercial FundingFunding II, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-AB, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 18, 20052006, between Principal Commercial Funding, LLC Morgan Stanley Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Commerxxxx Xoxxxxxx Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxler agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April October 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent agent, certificate rexxxxxar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP24 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnxxxxxxtxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agxxxxxxx, between Purchaser and the Underwriters, dated April 19October 18, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInxxxxx Pxxxxxxxrs") pursuant tx x Xxrxxxxxxxe Purchase to a Certificate Xxxxxxse Agreement, between Purchaser and the Initial Purchasers, dated April 19October 18, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2September 13, 20052006, as supplemented by a Prospectus Supplement dated April 19October 18, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 18, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:: AGREEMENT TO PURCHASE. SELLER AGREES TO SELL, AND PURCHASER AGREES TO PURCHASE, ON A SERVICING RELEASED BASIS, THE MORTGAGE LOANS IDENTIFIED ON THE SCHEDULE (THE "MORTGAGE LOAN SCHEDULE") ANNEXED HERETO AS EXHIBIT 1, AS SUCH SCHEDULE MAY BE AMENDED TO REFLECT THE ACTUAL MORTGAGE LOANS ACCEPTED BY PURCHASER PURSUANT TO THE TERMS HEREOF. THE CUT-OFF DATE WITH RESPECT TO THE MORTGAGE LOANS IS OCTOBER 1, 2006. THE MORTGAGE LOANS WILL HAVE AN AGGREGATE PRINCIPAL BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF $1,534,723,955. THE SALE OF THE MORTGAGE LOANS SHALL TAKE PLACE ON OCTOBER 31, 2006 OR SUCH OTHER DATE AS SHALL BE MUTUALLY ACCEPTABLE TO THE PARTIES HERETO (THE "CLOSING DATE"). THE PURCHASE PRICE TO BE PAID BY PURCHASER FOR THE MORTGAGE LOANS SHALL EQUAL THE AMOUNT SET FORTH AS SUCH PURCHASE PRICE ON EXHIBIT 3 HERETO. THE PURCHASE PRICE SHALL BE PAID TO SELLER BY WIRE TRANSFER IN IMMEDIATELY AVAILABLE FUNDS ON THE CLOSING DATE. ON THE CLOSING DATE, PURCHASER WILL ASSIGN TO THE TRUSTEE PURSUANT TO THE POOLING AND SERVICING AGREEMENT ALL OF ITS RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND ITS RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF), AND THE TRUSTEE SHALL SUCCEED TO SUCH RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND PURCHASER'S RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF). CONVEYANCE OF MORTGAGE LOANS. EFFECTIVE AS OF THE CLOSING DATE, SUBJECT ONLY TO RECEIPT OF THE CONSIDERATION REFERRED TO IN SECTION 1 HEREOF AND THE SATISFACTION OF THE CONDITIONS SPECIFIED IN SECTIONS 6 AND 7 HEREOF, SELLER DOES HEREBY TRANSFER, ASSIGN, SET OVER AND OTHERWISE CONVEY TO PURCHASER, WITHOUT RECOURSE, EXCEPT AS SPECIFICALLY PROVIDED HEREIN ALL THE RIGHT, TITLE AND INTEREST OF SELLER, WITH THE UNDERSTANDING THAT A SERVICING RIGHTS PURCHASE AND SALE AGREEMENT, DATED OCTOBER 1, 2006, WILL BE EXECUTED BY SELLER AND THE MASTER SERVICER, IN AND TO THE MORTGAGE LOANS IDENTIFIED ON THE MORTGAGE LOAN SCHEDULE AS OF THE CLOSING DATE. THE MORTGAGE LOAN SCHEDULE, AS IT MAY BE AMENDED FROM TIME TO TIME ON OR PRIOR TO THE CLOSING DATE, SHALL CONFORM TO THE REQUIREMENTS OF THIS AGREEMENT AND THE POOLING AND SERVICING AGREEMENT. IN CONNECTION WITH SUCH TRANSFER AND ASSIGNMENT, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE, ON BEHALF OF PURCHASER, ON OR PRIOR TO THE CLOSING DATE, THE MORTGAGE NOTE (AS DESCRIBED IN CLAUSE 2.2.1 HEREOF) FOR EACH MORTGAGE LOAN AND ON OR PRIOR TO THE FIFTH BUSINESS DAY AFTER THE CLOSING DATE, FIVE LIMITED POWERS OF ATTORNEY SUBSTANTIALLY IN THE FORM ATTACHED HERETO AS EXHIBIT 5 IN FAVOR OF THE TRUSTEE AND THE SPECIAL SERVICER TO EMPOWER THE TRUSTEE AND, IN THE EVENT OF THE FAILURE OR INCAPACITY OF THE TRUSTEE, THE SPECIAL SERVICER, TO SUBMIT FOR RECORDING, AT THE EXPENSE OF SELLER, ANY MORTGAGE LOAN DOCUMENTS REQUIRED TO BE RECORDED AS DESCRIBED IN THE POOLING AND SERVICING AGREEMENT AND ANY INTERVENING ASSIGNMENTS WITH EVIDENCE OF RECORDING THEREON THAT ARE REQUIRED TO BE INCLUDED IN THE MORTGAGE FILES (SO LONG AS ORIGINAL COUNTERPARTS HAVE PREVIOUSLY BEEN DELIVERED TO THE TRUSTEE). SELLER AGREES TO REASONABLY COOPERATE WITH THE TRUSTEE AND THE SPECIAL SERVICER IN CONNECTION WITH ANY ADDITIONAL POWERS OF ATTORNEY OR REVISIONS THERETO THAT ARE REQUESTED BY SUCH PARTIES FOR PURPOSES OF SUCH RECORDATION. THE PARTIES HERETO AGREE THAT NO SUCH POWER OF ATTORNEY SHALL BE USED WITH RESPECT TO ANY MORTGAGE LOAN BY OR UNDER AUTHORIZATION BY ANY PARTY HERETO EXCEPT TO THE EXTENT THAT THE ABSENCE OF A DOCUMENT DESCRIBED IN THE SECOND PRECEDING SENTENCE WITH RESPECT TO SUCH MORTGAGE LOAN REMAINS UNREMEDIED AS OF THE EARLIER OF (I) THE DATE THAT IS 180 DAYS FOLLOWING THE DELIVERY OF NOTICE OF SUCH ABSENCE TO SELLER, BUT IN NO EVENT EARLIER THAN 18 MONTHS FROM THE CLOSING DATE, AND (II) THE DATE (IF ANY) ON WHICH SUCH MORTGAGE LOAN BECOMES A SPECIALLY SERVICED MORTGAGE LOAN. THE TRUSTEE SHALL SUBMIT SUCH DOCUMENTS, AT SELLER'S EXPENSE, AFTER THE PERIODS SET FORTH ABOVE, PROVIDED, HOWEVER, THE TRUSTEE SHALL NOT SUBMIT SUCH ASSIGNMENTS FOR RECORDING IF SELLER PRODUCES EVIDENCE THAT IT HAS SENT ANY SUCH ASSIGNMENT FOR RECORDING AND CERTIFIES THAT SELLER IS AWAITING ITS RETURN FROM THE APPLICABLE RECORDING OFFICE. IN ADDITION, NOT LATER THAN THE 30TH DAY FOLLOWING THE CLOSING DATE, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE EACH OF THE REMAINING DOCUMENTS OR INSTRUMENTS SPECIFIED IN SECTION 2.2 HEREOF (WITH SUCH EXCEPTIONS AS ARE PERMITTED BY THIS SECTION 2) WITH RESPECT TO EACH MORTGAGE LOAN (EACH, A "MORTGAGE FILE"). (SELLER ACKNOWLEDGES THAT THE TERM "WITHOUT RECOURSE" DOES NOT MODIFY THE DUTIES OF SELLER UNDER SECTION 5 HEREOF.) ALL MORTGAGE FILES, OR PORTIONS THEREOF, DELIVERED PRIOR TO THE CLOSING DATE ARE TO BE HELD BY OR ON BEHALF OF THE TRUSTEE IN ESCROW ON BEHALF OF SELLER AT ALL TIMES PRIOR TO THE CLOSING DATE. THE MORTGAGE FILES SHALL BE RELEASED FROM ESCROW UPON CLOSING OF THE SALE OF THE MORTGAGE LOANS AND PAYMENTS OF THE PURCHASE PRICE THEREFOR AS CONTEMPLATED HEREBY. THE MORTGAGE FILE FOR EACH MORTGAGE LOAN SHALL CONTAIN THE FOLLOWING DOCUMENTS: THE ORIGINAL MORTGAGE NOTE BEARING ALL INTERVENING ENDORSEMENTS, ENDORSED "PAY TO THE ORDER OF LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24, WITHOUT RECOURSE, REPRESENTATION OR WARRANTY" OR IF THE ORIGINAL MORTGAGE NOTE IS NOT INCLUDED THEREIN, THEN A LOST NOTE AFFIDAVIT, WITH A COPY OF THE MORTGAGE NOTE ATTACHED THERETO; THE ORIGINAL MORTGAGE, WITH EVIDENCE OF RECORDING THEREON, AND, IF THE MORTGAGE WAS EXECUTED PURSUANT TO A POWER OF ATTORNEY, A CERTIFIED TRUE COPY OF THE POWER OF ATTORNEY CERTIFIED BY THE PUBLIC RECORDER'S OFFICE, WITH EVIDENCE OF RECORDING THEREON (IF RECORDING IS CUSTOMARY IN THE JURISDICTION IN WHICH SUCH POWER OF ATTORNEY WAS EXECUTED), OR CERTIFIED BY A TITLE INSURANCE COMPANY OR ESCROW COMPANY TO BE A TRUE COPY THEREOF; PROVIDED THAT IF SUCH ORIGINAL MORTGAGE CANNOT BE DELIVERED WITH EVIDENCE OF RECORDING THEREON ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE BECAUSE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE WHERE SUCH ORIGINAL MORTGAGE HAS BEEN DELIVERED FOR RECORDATION OR BECAUSE SUCH ORIGINAL MORTGAGE HAS BEEN LOST, SELLER SHALL DELIVER OR CAUSE TO BE DELIVERED TO THE TRUSTEE A TRUE AND CORRECT COPY OF SUCH MORTGAGE, TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE (AS DEFINED BELOW) OF SELLER STATING THAT SUCH ORIGINAL MORTGAGE HAS BEEN SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL MORTGAGE THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH MORTGAGE IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED MORTGAGE; THE ORIGINALS OF ALL AGREEMENTS MODIFYING A MONEY TERM OR OTHER MATERIAL MODIFICATION, CONSOLIDATION AND EXTENSION AGREEMENTS, IF ANY, WITH EVIDENCE OF RECORDING THEREON, OR IF ANY SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DELIVERED TO THE APPROPRIATE RECORDING OFFICE FOR RECORDATION AND EITHER HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE WITH EVIDENCE OF RECORDATION THEREON OR HAS BEEN LOST AFTER RECORDATION, A TRUE COPY OF SUCH MODIFICATION, CONSOLIDATION OR EXTENSION CERTIFIED BY SELLER TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DISPATCHED OR SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH DOCUMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT, AND THE ORIGINALS OF ALL ASSUMPTION AGREEMENTS, IF ANY; AN ORIGINAL ASSIGNMENT OF MORTGAGE FOR EACH MORTGAGE LOAN, IN FORM AND SUBSTANCE ACCEPTABLE FOR RECORDING, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24," PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MORTGAGE ELECTRONIC REGISTRATION SYSTEMS, INC. ("MERS") OR ITS DESIGNEE, NO SUCH ASSIGNMENTS WILL BE REQUIRED TO BE SUBMITTED FOR RECORDING OR FILING AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; ORIGINALS OF ALL INTERVENING ASSIGNMENTS OF MORTGAGE (EXCEPT WITH RESPECT TO ANY MORTGAGE THAT HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEES), IF ANY, WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ORIGINAL ASSIGNMENTS OF MORTGAGE HAVE BEEN DELIVERED TO THE APPROPRIATE RECORDER'S OFFICE FOR RECORDATION, CERTIFIED TRUE COPIES OF SUCH ASSIGNMENTS OF MORTGAGE CERTIFIED BY SELLER, OR IN THE CASE OF AN ORIGINAL BLANKET INTERVENING ASSIGNMENT OF MORTGAGE RETAINED BY SELLER, A COPY THEREOF CERTIFIED BY SELLER OR, IF ANY ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE RECORDING OFFICE OR HAS BEEN LOST, A TRUE AND CORRECT COPY THEREOF, TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS BEEN SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH ASSIGNMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED INTERVENING ASSIGNMENT OF MORTGAGE; IF THE RELATED ASSIGNMENT OF LEASES IS SEPARATE FROM THE MORTGAGE, THE ORIGINAL OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT OF LEASES CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT OF LEASES SUBMITTED FOR RECORDING, TOGETHER WITH (I) AN ORIGINAL OF EACH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON AND SHOWING A COMPLETE RECORDED CHAIN OF ASSIGNMENT FROM THE NAMED ASSIGNEE TO THE HOLDER OF RECORD, AND IF ANY SUCH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT SUBMITTED FOR RECORDING, AND (II) AN ORIGINAL ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES, IN RECORDABLE FORM, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24," WHICH ASSIGNMENT MAY BE EFFECTED IN THE RELATED ASSIGNMENT OF MORTGAGE, PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEE, NO ASSIGNMENT OF ASSIGNMENT OF LEASES IN FAVOR OF THE TRUSTEE WILL BE REQUIRED TO BE RECORDED OR DELIVERED AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; THE ORIGINAL OF EACH GUARANTY, IF ANY, CONSTITUTING ADDITIONAL SECURITY FOR THE REPAYMENT OF SUCH MORTGAGE LOAN; THE ORIGINAL TITLE INSURANCE POLICY, OR IN THE EVENT SUCH ORIGINAL TITLE INSURANCE POLICY HAS NOT BEEN ISSUED, AN ORIGINAL BINDER OR ACTUAL TITLE COMMITMENT OR A COPY THEREOF CERTIFIED BY THE TITLE COMPANY WITH THE ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE OR A PRELIMINARY TITLE REPORT BINDING ON THE TITLE COMPANY WITH AN ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE;

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19October 20, 2005, between Principal Commercial Funding, LLC Xxxxxx Xxxxxxx Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April October 1, 2005 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), Wells Xxxxx Fargo Bank, National Association, as paying agent and certificate xxxxstrar registrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent"). In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Xxxxxxx Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 2005-TOP18 TOP20 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4X-0X, Class A-4FLXxxxx X-0X, Class AXxxxx X-JX, Class B, Class C C, Class D and Class D E Certificates (the "Public Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19October 20, 2005 (the "Underwriting Agreement"), and the Class X, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class Q, Class LF, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley Xxxxxx Xxxxxxx & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19October 20, 2005 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March September 2, 2005, as supplemented by a Prospectus Supplement dated April 19October 20, 2005 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 20, 2005 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Commercial FundingFunding II, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Wxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Wxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-AB, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:: AGREEMENT TO PURCHASE. SELLER AGREES TO SELL, AND PURCHASER AGREES TO PURCHASE, ON A SERVICING RELEASED BASIS, THE MORTGAGE LOANS IDENTIFIED ON THE SCHEDULE (THE "MORTGAGE LOAN SCHEDULE") ANNEXED HERETO AS EXHIBIT 1, AS SUCH SCHEDULE MAY BE AMENDED TO REFLECT THE ACTUAL MORTGAGE LOANS ACCEPTED BY PURCHASER PURSUANT TO THE TERMS HEREOF. THE CUT-OFF DATE WITH RESPECT TO THE MORTGAGE LOANS IS JANUARY 1, 2007. THE MORTGAGE LOANS WILL HAVE AN AGGREGATE PRINCIPAL BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF (I) $329,133,538, PLUS (II) THE 50% PARI PASSU INTEREST OF THE SELLER IN THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN, WHICH SUCH PARI PASSU INTEREST IS REPRESENTED BY THE RELATED MORTGAGE NOTE WITH A CUT-OFF DATE BALANCE OF $23,375,000. SELLER AND MXXXXX SXXXXXX MORTGAGE CAPITAL INC. CO-ORIGINATED THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN, WHICH WILL HAVE AN AGGREGATE BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF $46,750,000. THE SALE OF THE MORTGAGE LOANS SHALL TAKE PLACE ON JANUARY 30, 2007 OR SUCH OTHER DATE AS SHALL BE MUTUALLY ACCEPTABLE TO THE PARTIES HERETO (THE "CLOSING DATE"). THE PURCHASE PRICE TO BE PAID BY PURCHASER FOR THE MORTGAGE LOANS SHALL EQUAL THE AMOUNT SET FORTH AS SUCH PURCHASE PRICE ON EXHIBIT 3 HERETO. THE PURCHASE PRICE SHALL BE PAID TO SELLER BY WIRE TRANSFER IN IMMEDIATELY AVAILABLE FUNDS ON THE CLOSING DATE. NOTWITHSTANDING ANYTHING TO THE CONTRARY CONTAINED HEREIN, WITH RESPECT TO THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN, REFERENCES TO A MORTGAGE NOTE HEREIN SHALL MEAN THE MORTGAGE NOTE RELATED TO THE 400 XXXXX XXXXXXX XXXXX MORTGAGE LOAN. ON THE CLOSING DATE, PURCHASER WILL ASSIGN TO THE TRUSTEE PURSUANT TO THE POOLING AND SERVICING AGREEMENT ALL OF ITS RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND ITS RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF), AND THE TRUSTEE SHALL SUCCEED TO SUCH RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND PURCHASER'S RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF). CONVEYANCE OF MORTGAGE LOANS. EFFECTIVE AS OF THE CLOSING DATE, SUBJECT ONLY TO RECEIPT OF THE CONSIDERATION REFERRED TO IN SECTION 1 HEREOF AND THE SATISFACTION OF THE CONDITIONS SPECIFIED IN SECTIONS 6 AND 7 HEREOF, SELLER DOES HEREBY TRANSFER, ASSIGN, SET OVER AND OTHERWISE CONVEY TO PURCHASER, WITHOUT RECOURSE, EXCEPT AS SPECIFICALLY PROVIDED HEREIN ALL THE RIGHT, TITLE AND INTEREST OF SELLER, WITH THE UNDERSTANDING THAT A SERVICING RIGHTS PURCHASE AND SALE AGREEMENT, DATED JANUARY 1, 2007, WILL BE EXECUTED BY SELLER AND THE MASTER SERVICER, IN AND TO THE MORTGAGE LOANS IDENTIFIED ON THE MORTGAGE LOAN SCHEDULE AS OF THE CLOSING DATE. THE MORTGAGE LOAN SCHEDULE, AS IT MAY BE AMENDED FROM TIME TO TIME ON OR PRIOR TO THE CLOSING DATE, SHALL CONFORM TO THE REQUIREMENTS OF THIS AGREEMENT AND THE POOLING AND SERVICING

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 196, 20052006, between Principal Commercial Funding, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxxxx agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")xxxxstrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnxxxxxxtxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agxxxxxxx, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInxxxxx Pxxxxxxxrs") pursuant tx x Xxrxxxxxxxe Purchase to a Certificate Xxxxxxse Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19February 13, 20052008, between Principal Commercial FundingFunding II, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April February 1, 2005 2008 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052008-TOP18 TOP29 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-4FL and Class A-J, Class B, Class C and Class D M Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19February 13, 2005 2008 (the "Underwriting Agreement"), and the Class X, Class A-J1, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19February 13, 2005 2008 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2February 1, 20052008, as supplemented by a Prospectus Supplement dated April 19February 13, 2005 2008 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19February 13, 2005 2008 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL WXXXX LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April January 19, 20052007, between Principal Commercial FundingWxxxx Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2007 between Purchaser, as depositor, Wells Wxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Wxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Mxxxxx Sxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052007-TOP18 TOP25 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-1A, Class A-2, Class A-AB, Class A-3, Class A-AB, Class A-4, Class A-4FL, M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April January 19, 2005 2007 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Mxxxxx Sxxxxxx & Co. Incorporated and Bear, Stearns Sxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April January 19, 2005 2007 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 214, 20052006, as supplemented by a Prospectus Supplement dated April January 19, 2005 2007 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April January 19, 2005 2007 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19January 20, 20052006, between Principal Commercial Funding, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc. ("Purchaser"). Seller agrexx xx xell and Purchaser agrees to sexx xxx Xxxxxxxer agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April January 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerXxxxxr Servicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certixxxxxe registrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Morgan Stanley Capital I Inc., Commercial Mortgage Pass-Txxxxxx CertificatesThrough Cxxxxxxcxxxx, Series 2005Xeries 2006-TOP18 TOP21 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "UnderwrixxxxXxdxxxxxxxrs"), pursuant to an Xxxxxxrxxxxx XgreementUnderwritxxx Xxxeement, between Purchaser and the Underwriters, dated April 19January 20, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class MM-NA, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the txx "Initial XxxxxxxersXxixxxx Xxrchasers") pursuant tx x Xxrxxxxxxxe to a Certixxxxxx Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19January 20, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2June 7, 2005, as supplemented by a Prospectus Supplement dated April 19January 20, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19January 20, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL WELLS LOANS) Mortgage Loan Purchase Agreement ("AgreementAgreemxxx"), dated as of April 19October 18, 20052006, between Principal Commercial FundingWells Fargo Bank, LLC National Association ("Seller"), ) and Bear Stearns Commercial Commxxxxxl Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxler agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April October 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent agent, certificate rexxxxxar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP24 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-M and Class A-J, Class B, Class C and Class D J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnxxxxxxtxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agxxxxxxx, between Purchaser and the Underwriters, dated April 19October 18, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInxxxxx Pxxxxxxxrs") pursuant tx x Xxrxxxxxxxe Purchase to a Certificate Xxxxxxse Agreement, between Purchaser and the Initial Purchasers, dated April 19October 18, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2September 13, 20052006, as supplemented by a Prospectus Supplement dated April 19October 18, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19October 18, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:: AGREEMENT TO PURCHASE. SELLER AGREES TO SELL, AND PURCHASER AGREES TO PURCHASE, ON A SERVICING RELEASED BASIS, THE MORTGAGE LOANS IDENTIFIED ON THE SCHEDULE (THE "MORTGAGE LOAN SCHEDULE") ANNEXED HERETO AS EXHIBIT 1, AS SUCH SCHEDULE MAY BE AMENDED TO REFLECT THE ACTUAL MORTGAGE LOANS ACCEPTED BY PURCHASER PURSUANT TO THE TERMS HEREOF. THE CUT-OFF DATE WITH RESPECT TO THE MORTGAGE LOANS IS OCTOBER 1, 2006. THE MORTGAGE LOANS WILL HAVE AN AGGREGATE PRINCIPAL BALANCE AS OF THE CLOSE OF BUSINESS ON THE CUT-OFF DATE, AFTER GIVING EFFECT TO ANY PAYMENTS DUE ON OR BEFORE SUCH DATE, WHETHER OR NOT RECEIVED, OF $1,534,723,955. THE SALE OF THE MORTGAGE LOANS SHALL TAKE PLACE ON OCTOBER 31, 2006 OR SUCH OTHER DATE AS SHALL BE MUTUALLY ACCEPTABLE TO THE PARTIES HERETO (THE "CLOSING DATE"). THE PURCHASE PRICE TO BE PAID BY PURCHASER FOR THE MORTGAGE LOANS SHALL EQUAL THE AMOUNT SET FORTH AS SUCH PURCHASE PRICE ON EXHIBIT 3 HERETO. THE PURCHASE PRICE SHALL BE PAID TO SELLER BY WIRE TRANSFER IN IMMEDIATELY AVAILABLE FUNDS ON THE CLOSING DATE. ON THE CLOSING DATE, PURCHASER WILL ASSIGN TO THE TRUSTEE PURSUANT TO THE POOLING AND SERVICING AGREEMENT ALL OF ITS RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND ITS RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF), AND THE TRUSTEE SHALL SUCCEED TO SUCH RIGHT, TITLE AND INTEREST IN AND TO THE MORTGAGE LOANS AND PURCHASER'S RIGHTS UNDER THIS AGREEMENT (TO THE EXTENT SET FORTH IN SECTION 14 HEREOF). CONVEYANCE OF MORTGAGE LOANS. EFFECTIVE AS OF THE CLOSING DATE, SUBJECT ONLY TO RECEIPT OF THE CONSIDERATION REFERRED TO IN SECTION 1 HEREOF AND THE SATISFACTION OF THE CONDITIONS SPECIFIED IN SECTIONS 6 AND 7 HEREOF, SELLER DOES HEREBY TRANSFER, ASSIGN, SET OVER AND OTHERWISE CONVEY TO PURCHASER, WITHOUT RECOURSE, EXCEPT AS SPECIFICALLY PROVIDED HEREIN ALL THE RIGHT, TITLE AND INTEREST OF SELLER, WITH THE UNDERSTANDING THAT A SERVICING RIGHTS PURCHASE AND SALE AGREEMENT, DATED OCTOBER 1, 2006, WILL BE EXECUTED BY SELLER AND THE MASTER SERVICER, IN AND TO THE MORTGAGE LOANS IDENTIFIED ON THE MORTGAGE LOAN SCHEDULE AS OF THE CLOSING DATE. THE MORTGAGE LOAN SCHEDULE, AS IT MAY BE AMENDED FROM TIME TO TIME ON OR PRIOR TO THE CLOSING DATE, SHALL CONFORM TO THE REQUIREMENTS OF THIS AGREEMENT AND THE POOLING AND SERVICING AGREEMENT. IN CONNECTION WITH SUCH TRANSFER AND ASSIGNMENT, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE, ON BEHALF OF PURCHASER, ON OR PRIOR TO THE CLOSING DATE, THE MORTGAGE NOTE (AS DESCRIBED IN CLAUSE 2.2.1 HEREOF) FOR EACH MORTGAGE LOAN AND ON OR PRIOR TO THE FIFTH BUSINESS DAY AFTER THE CLOSING DATE, FIVE LIMITED POWERS OF ATTORNEY SUBSTANTIALLY IN THE FORM ATTACHED HERETO AS EXHIBIT 5 IN FAVOR OF THE TRUSTEE AND THE SPECIAL SERVICER TO EMPOWER THE TRUSTEE AND, IN THE EVENT OF THE FAILURE OR INCAPACITY OF THE TRUSTEE, THE SPECIAL SERVICER, TO SUBMIT FOR RECORDING, AT THE EXPENSE OF SELLER, ANY MORTGAGE LOAN DOCUMENTS REQUIRED TO BE RECORDED AS DESCRIBED IN THE POOLING AND SERVICING AGREEMENT AND ANY INTERVENING ASSIGNMENTS WITH EVIDENCE OF RECORDING THEREON THAT ARE REQUIRED TO BE INCLUDED IN THE MORTGAGE FILES (SO LONG AS ORIGINAL COUNTERPARTS HAVE PREVIOUSLY BEEN DELIVERED TO THE TRUSTEE). SELLER AGREES TO REASONABLY COOPERATE WITH THE TRUSTEE AND THE SPECIAL SERVICER IN CONNECTION WITH ANY ADDITIONAL POWERS OF ATTORNEY OR REVISIONS THERETO THAT ARE REQUESTED BY SUCH PARTIES FOR PURPOSES OF SUCH RECORDATION. THE PARTIES HERETO AGREE THAT NO SUCH POWER OF ATTORNEY SHALL BE USED WITH RESPECT TO ANY MORTGAGE LOAN BY OR UNDER AUTHORIZATION BY ANY PARTY HERETO EXCEPT TO THE EXTENT THAT THE ABSENCE OF A DOCUMENT DESCRIBED IN THE SECOND PRECEDING SENTENCE WITH RESPECT TO SUCH MORTGAGE LOAN REMAINS UNREMEDIED AS OF THE EARLIER OF (I) THE DATE THAT IS 180 DAYS FOLLOWING THE DELIVERY OF NOTICE OF SUCH ABSENCE TO SELLER, BUT IN NO EVENT EARLIER THAN 18 MONTHS FROM THE CLOSING DATE, AND (II) THE DATE (IF ANY) ON WHICH SUCH MORTGAGE LOAN BECOMES A SPECIALLY SERVICED MORTGAGE LOAN. THE TRUSTEE SHALL SUBMIT SUCH DOCUMENTS, AT SELLER'S EXPENSE, AFTER THE PERIODS SET FORTH ABOVE, PROVIDED, HOWEVER, THE TRUSTEE SHALL NOT SUBMIT SUCH ASSIGNMENTS FOR RECORDING IF SELLER PRODUCES EVIDENCE THAT IT HAS SENT ANY SUCH ASSIGNMENT FOR RECORDING AND CERTIFIES THAT SELLER IS AWAITING ITS RETURN FROM THE APPLICABLE RECORDING OFFICE. IN ADDITION, NOT LATER THAN THE 30TH DAY FOLLOWING THE CLOSING DATE, SELLER SHALL DELIVER TO OR ON BEHALF OF THE TRUSTEE EACH OF THE REMAINING DOCUMENTS OR INSTRUMENTS SPECIFIED IN SECTION 2.2 HEREOF (WITH SUCH EXCEPTIONS AS ARE PERMITTED BY THIS SECTION 2) WITH RESPECT TO EACH MORTGAGE LOAN (EACH, A "MORTGAGE FILE"). (SELLER ACKNOWLEDGES THAT THE TERM "WITHOUT RECOURSE" DOES NOT MODIFY THE DUTIES OF SELLER UNDER SECTION 5 HEREOF.) ALL MORTGAGE FILES, OR PORTIONS THEREOF, DELIVERED PRIOR TO THE CLOSING DATE ARE TO BE HELD BY OR ON BEHALF OF THE TRUSTEE IN ESCROW ON BEHALF OF SELLER AT ALL TIMES PRIOR TO THE CLOSING DATE. THE MORTGAGE FILES SHALL BE RELEASED FROM ESCROW UPON CLOSING OF THE SALE OF THE MORTGAGE LOANS AND PAYMENTS OF THE PURCHASE PRICE THEREFOR AS CONTEMPLATED HEREBY. THE MORTGAGE FILE FOR EACH MORTGAGE LOAN SHALL CONTAIN THE FOLLOWING DOCUMENTS: THE ORIGINAL MORTGAGE NOTE BEARING ALL INTERVENING ENDORSEMENTS, ENDORSED "PAY TO THE ORDER OF LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24, WITHOUT RECOURSE, REPRESENTATION OR WARRANTY" OR IF THE ORIGINAL MORTGAGE NOTE IS NOT INCLUDED THEREIN, THEN A LOST NOTE AFFIDAVIT, WITH A COPY OF THE MORTGAGE NOTE ATTACHED THERETO; THE ORIGINAL MORTGAGE, WITH EVIDENCE OF RECORDING THEREON, AND, IF THE MORTGAGE WAS EXECUTED PURSUANT TO A POWER OF ATTORNEY, A CERTIFIED TRUE COPY OF THE POWER OF ATTORNEY CERTIFIED BY THE PUBLIC RECORDER'S OFFICE, WITH EVIDENCE OF RECORDING THEREON (IF RECORDING IS CUSTOMARY IN THE JURISDICTION IN WHICH SUCH POWER OF ATTORNEY WAS EXECUTED), OR CERTIFIED BY A TITLE INSURANCE COMPANY OR ESCROW COMPANY TO BE A TRUE COPY THEREOF; PROVIDED THAT IF SUCH ORIGINAL MORTGAGE CANNOT BE DELIVERED WITH EVIDENCE OF RECORDING THEREON ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE BECAUSE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE WHERE SUCH ORIGINAL MORTGAGE HAS BEEN DELIVERED FOR RECORDATION OR BECAUSE SUCH ORIGINAL MORTGAGE HAS BEEN LOST, SELLER SHALL DELIVER OR CAUSE TO BE DELIVERED TO THE TRUSTEE A TRUE AND CORRECT COPY OF SUCH MORTGAGE, TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE (AS DEFINED BELOW) OF SELLER STATING THAT SUCH ORIGINAL MORTGAGE HAS BEEN SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL MORTGAGE THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH MORTGAGE IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED MORTGAGE; THE ORIGINALS OF ALL AGREEMENTS MODIFYING A MONEY TERM OR OTHER MATERIAL MODIFICATION, CONSOLIDATION AND EXTENSION AGREEMENTS, IF ANY, WITH EVIDENCE OF RECORDING THEREON, OR IF ANY SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DELIVERED TO THE APPROPRIATE RECORDING OFFICE FOR RECORDATION AND EITHER HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE WITH EVIDENCE OF RECORDATION THEREON OR HAS BEEN LOST AFTER RECORDATION, A TRUE COPY OF SUCH MODIFICATION, CONSOLIDATION OR EXTENSION CERTIFIED BY SELLER TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT HAS BEEN DISPATCHED OR SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH DOCUMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED MODIFICATION, CONSOLIDATION OR EXTENSION AGREEMENT, AND THE ORIGINALS OF ALL ASSUMPTION AGREEMENTS, IF ANY; AN ORIGINAL ASSIGNMENT OF MORTGAGE FOR EACH MORTGAGE LOAN, IN FORM AND SUBSTANCE ACCEPTABLE FOR RECORDING, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24," PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MORTGAGE ELECTRONIC REGISTRATION SYSTEMS, INC. ("MERS") OR ITS DESIGNEE, NO SUCH ASSIGNMENTS WILL BE REQUIRED TO BE SUBMITTED FOR RECORDING OR FILING AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; ORIGINALS OF ALL INTERVENING ASSIGNMENTS OF MORTGAGE (EXCEPT WITH RESPECT TO ANY MORTGAGE THAT HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEES), IF ANY, WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ORIGINAL ASSIGNMENTS OF MORTGAGE HAVE BEEN DELIVERED TO THE APPROPRIATE RECORDER'S OFFICE FOR RECORDATION, CERTIFIED TRUE COPIES OF SUCH ASSIGNMENTS OF MORTGAGE CERTIFIED BY SELLER, OR IN THE CASE OF AN ORIGINAL BLANKET INTERVENING ASSIGNMENT OF MORTGAGE RETAINED BY SELLER, A COPY THEREOF CERTIFIED BY SELLER OR, IF ANY ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS NOT YET BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE RECORDING OFFICE OR HAS BEEN LOST, A TRUE AND CORRECT COPY THEREOF, TOGETHER WITH (I) IN THE CASE OF A DELAY CAUSED BY THE PUBLIC RECORDING OFFICE, AN OFFICER'S CERTIFICATE OF SELLER STATING THAT SUCH ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE HAS BEEN SENT TO THE APPROPRIATE PUBLIC RECORDING OFFICIAL FOR RECORDATION OR (II) IN THE CASE OF AN ORIGINAL INTERVENING ASSIGNMENT OF MORTGAGE THAT HAS BEEN LOST AFTER RECORDATION, A CERTIFICATION BY THE APPROPRIATE COUNTY RECORDING OFFICE WHERE SUCH ASSIGNMENT IS RECORDED THAT SUCH COPY IS A TRUE AND COMPLETE COPY OF THE ORIGINAL RECORDED INTERVENING ASSIGNMENT OF MORTGAGE; IF THE RELATED ASSIGNMENT OF LEASES IS SEPARATE FROM THE MORTGAGE, THE ORIGINAL OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON OR, IF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED ON OR PRIOR TO THE 45TH DAY FOLLOWING THE CLOSING DATE FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT OF LEASES CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT OF LEASES SUBMITTED FOR RECORDING, TOGETHER WITH (I) AN ORIGINAL OF EACH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES WITH EVIDENCE OF RECORDING THEREON AND SHOWING A COMPLETE RECORDED CHAIN OF ASSIGNMENT FROM THE NAMED ASSIGNEE TO THE HOLDER OF RECORD, AND IF ANY SUCH ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES HAS NOT BEEN RETURNED FROM THE APPLICABLE PUBLIC RECORDING OFFICE, A COPY OF SUCH ASSIGNMENT CERTIFIED BY SELLER TO BE A TRUE AND COMPLETE COPY OF THE ORIGINAL ASSIGNMENT SUBMITTED FOR RECORDING, AND (II) AN ORIGINAL ASSIGNMENT OF SUCH ASSIGNMENT OF LEASES, IN RECORDABLE FORM, SIGNED BY THE HOLDER OF RECORD IN FAVOR OF "LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR BEAR STEARNS COMMERCIAL MORTGAGE SECURITIES INC., COMMERCIAL MORTGAGE PASS-TXXXXXX CERTIFICATES, SERIES 2006-TOP24," WHICH ASSIGNMENT MAY BE EFFECTED IN THE RELATED ASSIGNMENT OF MORTGAGE, PROVIDED, IF THE RELATED MORTGAGE HAS BEEN RECORDED IN THE NAME OF MERS OR ITS DESIGNEE, NO ASSIGNMENT OF ASSIGNMENT OF LEASES IN FAVOR OF THE TRUSTEE WILL BE REQUIRED TO BE RECORDED OR DELIVERED AND INSTEAD, SELLER SHALL TAKE ALL ACTIONS AS ARE NECESSARY TO CAUSE THE TRUSTEE TO BE SHOWN AS THE OWNER OF THE RELATED MORTGAGE ON THE RECORD OF MERS FOR PURPOSES OF THE SYSTEM OF RECORDING TRANSFERS OF BENEFICIAL OWNERSHIP OF MORTGAGES MAINTAINED BY MERS AND SHALL DELIVER TO THE MASTER SERVICER AND THE SPECIAL SERVICER EVIDENCE CONFIRMING THAT THE TRUSTEE IS SHOWN AS THE OWNER ON THE RECORD OF MERS; THE ORIGINAL OF EACH GUARANTY, IF ANY, CONSTITUTING ADDITIONAL SECURITY FOR THE REPAYMENT OF SUCH MORTGAGE LOAN; THE ORIGINAL TITLE INSURANCE POLICY, OR IN THE EVENT SUCH ORIGINAL TITLE INSURANCE POLICY HAS NOT BEEN ISSUED, AN ORIGINAL BINDER OR ACTUAL TITLE COMMITMENT OR A COPY THEREOF CERTIFIED BY THE TITLE COMPANY WITH THE ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE OR A PRELIMINARY TITLE REPORT BINDING ON THE TITLE COMPANY WITH AN ORIGINAL TITLE INSURANCE POLICY TO FOLLOW WITHIN 180 DAYS OF THE CLOSING DATE;

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 196, 20052006, between Principal Commercial Funding, LLC Morgan Stanley Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Commerxxxx Xoxxxxxx Securities Inc. ("Purchaser"). Seller agrexx xx xell Xxxxxx agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master Xxxxicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")xxxxstrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage Pass-Txxxxxx Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnxxxxxxtxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agxxxxxxx, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersInxxxxx Pxxxxxxxrs") pursuant tx x Xxrxxxxxxxe Purchase to a Certificate Xxxxxxse Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL MSMC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 196, 20052006, between Principal Commercial Funding, LLC Morgan Stanley Mortgage Capital Inc. ("Seller"), ) and Bear Stearns Commercial Mortgage Comxxxxxxl Xxxxxxge Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certificxxx xegistrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxwxxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxent, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxax Xxxxxasers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificxxx Xxxchase Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 196, 20052006, between Principal Commercial Funding, LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Inc. ("Purchaser"). Seller agrexx xx xell axxxxx xo sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April 1, 2005 2006 between Purchaser, as depositor, Wells Fargo Bank, National Association, as master servicer (the "Master XxxxicerMasxxx Xervicer"), ARCap Servicing, Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee (the "Trustee"), ) and Wells Fargo Bank, National Association, as paying agent and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")certificxxx xegistrar. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Inc., Commercial Mortgage PassPasx-Txxxxxx Xxxxxgh Certificates, Series 20052006-TOP18 TOP22 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FLA-1A, Class A-J, Class B, Class C M and Class D A-J Certificates (the "Public Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxXxxxxwxxxxxx"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Xxxxxxent, between Purchaser and the Underwriters, dated April 196, 2005 2006 (the "Underwriting Agreement"), and the Class X, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Morgan Stanley & Co. Incorporated and Bear, Stearns & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersXxxxxax Xxxxxasers") pursuant tx x Xxrxxxxxxxe Purchase to a Certificxxx Xxxchase Agreement, between Purchaser and the Initial Purchasers, dated April 196, 2005 2006 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 231, 20052006, as supplemented by a Prospectus Supplement dated April 196, 2005 2006 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 196, 2005 2006 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows:

Underwriting Agreement. 1 2 MORTGAGE LOAN PURCHASE AGREEMENT (PRINCIPAL XXXXXX XXXXXXX MORTGAGE CAPITAL HOLDINGS LLC LOANS) Mortgage Loan Purchase Agreement ("Agreement"), dated as of April 19February 13, 20052008, between Principal Commercial Funding, Xxxxxx Xxxxxxx Mortgage Capital Holdings LLC ("Seller"), ) and Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc. ("Purchaser"). Seller agrexx xx xell agrees to sell and Purchaser agrees to purchase certain mortgage loans listed on Exhibit 1 hereto (the "Mortgage Loans") as described herein. Purchaser will convey the Mortgage Loans to a trust (the "Trust") created pursuant to a Pooling and Servicing Agreement (the "Pooling and Servicing Agreement"), to be dated as of April February 1, 2005 2008 between Purchaser, as depositor, Wells Xxxxx Fargo Bank, National Association, as master servicer (the "Master XxxxicerServicer"), ARCap Servicing, Centerline Servicing Inc., as special servicer (the "Special Servicer"), LaSalle Bank National Association, as trustee and custodian (the "Trustee"), Wells ) and Xxxxx Fargo Bank, National Association, as paying agent agent, certificate registrar and certificate xxxxstrar and ABN AMRO Bank N.V., as fiscal agent (the "Fiscal Agent")authenticating agent. In exchange for the Mortgage Loans and certain other mortgage loans to be purchased by Purchaser (collectively the "Other Mortgage Loans"), the Trust will issue to the Depositor pass-through certificates to be known as Bear Stearns Commercial Mortgage Securities Xxxxxx Xxxxxxx Capital I Inc., Commercial Mortgage Pass-Txxxxxx Through Certificates, Series 20052008-TOP18 TOP29 (the "Certificates"). The Certificates will be issued pursuant to the Pooling and Servicing Agreement. Capitalized terms used herein but not defined herein shall have the meanings assigned to them in the Pooling and Servicing Agreement. The Class A-1, Class A-2, Class A-3, Class A-AB, Class A-4, Class A-4FL, A-4FL and Class A-J, Class B, Class C and Class D M Certificates (the "Public Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "UnderwrixxxxUnderwriters"), pursuant to an Xxxxxxrxxxxx XgreementUnderwriting Agreement, between Purchaser and the Underwriters, dated April 19February 13, 2005 2008 (the "Underwriting Agreement"), and the Class X, Class A-J1, Class B, Class C, Class D, Class E, Class F, Class G, Class H, Class J, Class K, Class L, Class M, Class N, Class O, Class P, Class R-I, Class R-II and Class R-III Certificates (the "Private Certificates") will be sold by Purchaser to Xxxxxx Xxxxxxx & Co. Incorporated and Bear, Stearns Xxxxxxx & Co. Inc. and Morgan Stanley & Co. Incorporated (the "Initial XxxxxxxersPurchasers") pursuant tx x Xxrxxxxxxxe to a Certificate Purchase Agreement, between Purchaser and the Initial Purchasers, dated April 19February 13, 2005 2008 (the "Certificate Purchase Agreement"). The Underwriters will offer the Public Certificates for sale publicly pursuant to a Prospectus dated March 2February 1, 20052008, as supplemented by a Prospectus Supplement dated April 19February 13, 2005 2008 (together, the "Prospectus Supplement"), ) and the Initial Purchasers will offer the Private Certificates for sale in transactions exempt from the registration requirements of the Securities Act of 1933 pursuant to a Private Placement Memorandum dated April 19February 13, 2005 2008 (the "Memorandum"). In consideration of the mutual agreements contained herein, Seller and Purchaser hereby agree as follows: