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                                                                    EXHIBIT 10.1

                        THIRD AMENDMENT TO LOAN AGREEMENT

         THIS THIRD amendment to LOAN AGREEMENT (the "Agreement") is made and
entered into as of July 1, 2001 by and between Sun Communities Operating Limited
Partnership, a Michigan limited partnership ("Lender"), whose address is 31700
Middlebelt Road, Suite 145, Farmington Hills, Michigan 48334, and BINGHAM
FINANCIAL SERVICES CORPORATION, a Michigan corporation ("Borrower"), whose
address is 260 East Brown Street, Suite 200, Birmingham, MI 48009.

                                    RECITALS:

         A. Borrower and Lender have entered into that certain Loan Agreement
dated March 1, 1998, a First Amendment to Loan Agreement dated as of June 11,
1999 and a Second Amendment to Loan Agreement dated as of December 13, 1999
(collectively, the "Loan Agreement").

         B. Borrower and Lender desire to amend the Loan Agreement in accordance
with the terms and conditions of this Amendment.

         NOW, THEREFORE, the parties agree as follows:

         1. Section 1 of the Loan Agreement is hereby deleted in its entirety
and replaced with the following Section 1:

                  "1.      LOAN. Lender will make the following Loan to
                           Borrower:
<TABLE>
<CAPTION>
                   Type of Loan     Interest Rate      Note Amount     Maturity
                   ------------      -------------     ------------    --------
<S>                <C>              <C>                <C>             <C>
                   Line of Credit     8% per annum      $50,000,000     Demand
</TABLE>

                  The Loan and any amendments, extensions, renewals, or
         refinancing thereof are subject to this Agreement."

         2. Unless otherwise modified by this Amendment, all provisions of the
Loan Agreement shall remain in full force and effect.

         3. This Amendment may be executed in any number of counterparts, each
of which shall be an original and all of which together shall constitute one and
the same agreement. Facsimile or photographic reproductions of this Amendment
may be made and relied upon to the same extent as though such fax or copy were
an original.

                            [signature page attached]
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         IN WITNESS WHEREOF, the parties have executed this First Amendment to
Loan Agreement as of the date first written above.

                          BORROWER:

                          BINGHAM FINANCIAL SERVICES
                          CORPORATION, a Michigan corporation

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

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


                          LENDER:

                          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
                             -----------------------------------------


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