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                                                                   EXHIBIT 10.20

              AMENDMENT TO AMENDED AND RESTATED SECURITY AGREEMENT

     THIS AMENDMENT TO AMENDED AND RESTATED SECURITY AGREEMENT (the "Agreement")
is entered into this 20th day of October, 2000 by and between BINGHAM FINANCIAL
SERVICES CORPORATION, a Michigan corporation whose address is 260 E. Brown
Street, Suite 200, Birmingham, Michigan 48009 ("Borrower") and SUN COMMUNITIES
OPERATING LIMITED PARTNERSHIP, a Michigan Limited Partnership whose address is
31700 Middlebelt Road, Suite 145, Farmington Hills, MI 48334 ("Secured Party").

                                    RECITALS:

        A. Borrower previously executed a Security Agreement in favor of Secured
     Party dated December 13, 1999, which was subsequently amended by an Amended
     and Restated Security Agreement dated as of December 13, 1999 (the
     "Security Agreement");

        B. Borrower has acquired an equity interest in e-Cognita Technologies,
     Inc. ("e-Cognita") and contemporaneous therewith executed and delivered to
     Secured Party a Stock Pledge Agreement with respect to Borrower's interest
     in e-Cognita and delivered Borrower's share certificate evidencing such
     ownership and pledge; and

        C. Borrower has agreed, also contemporaneous with its acquisition of its
     interest in e-Cognita, to amend the Security Agreement to reflect
     Borrower's pledge and grant of a security interest in Borrower's interest
     in e-Cognita to Secured Party.

     THEREFORE, the parties hereby agree as follows:

     1. Paragraph 1(j) of the Security Agreement is hereby amended to read as
follows:

        "(j) "General Intangibles" means all "general intangibles", as such term
        is defined in Section 9-106 of the Code, in which Borrower now or
        hereafter has any right, title or interest. General Intangibles shall
        also include all equity interests of Borrower in other entities,
        including but not limited to membership interests in Bloomfield
        Acceptance Company, L.L.C. and Bloomfield Servicing Company, L.L.C.;
        stock interests in Dynex Financial, Inc., Hartger & Willard Associates,
        Inc. and e-Cognita Technologies, Inc.; and all partnership interests."

     2. This Agreement and all rights and obligations hereunder including
matters of construction, validity and performance, shall be governed by the laws
of the State of Michigan. This Agreement is intended to take effect when signed
by Borrower and delivered to Secured Party. This Agreement may be executed in
counterparts, each of which shall be deemed to be an original and all of which
together shall constitute one instrument. Facsimile copies of signatures to this
Agreement shall be deemed to be originals, and the parties may rely upon such
facsimile copies to the same extent as the originals.

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     IN WITNESS WHEREOF, the parties have executed this Agreement as of the day
and year above written.


                                  "BORROWER"

                                  BINGHAM FINANCIAL SERVICES
                                  CORPORATION, a Michigan corporation

                                  By: /s/ Ronald A. Klein
                                     -------------------------------------------

                                  Its: President and Chief Executive Officer
                                      ------------------------------------------


                                  "SECURED PARTY"

                                  SUN COMMUNITIES OPERATING LIMITED
                                  PARTNERSHIP,  a Michigan limited partnership


                                  By:  Sun Communities, Inc., a Maryland
                                       corporation
                                  Its: General Partner

                                  By:   /s/ Gary  A. Shiffman
                                     -------------------------------------------
                                  Its:  President and Chief Executive Officer
                                      ------------------------------------------



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                                    EXHIBIT A


            Liens, if any, in favor of Lehman Commercial Paper, Inc.



















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