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                                                                   EXHIBIT 10.12

                                 LOAN AGREEMENT

         THIS LOAN AGREEMENT (the "Agreement") is made and entered into as of
March 30, 1999 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, Michigan 48009.

                                    RECITAL:

         A.   Borrower has requested from Lender, and Lender has agreed to make
the loan described below (the "Loan") to Borrower, in accordance with the terms
and conditions set forth in this Agreement.

         NOW, THEREFORE, the parties agree as follows:

         1.   LOAN. Lender will make the following Loan to Borrower:

<TABLE>
<CAPTION>
Type of Loan          Interest Rate           Note Amount               Maturity
------------          -------------           -----------               --------
<S>                   <C>                     <C>                       <C>

Line of Credit        235 basis points        $10,000,000               Demand
                      over LIBOR

</TABLE>

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

         2.   LINE OF CREDIT DEMAND LOAN. Provided that no Event of Default
exists and no Event of Default will be caused by any draw under the Loan, Lender
agrees to loan to Borrower, from time to time upon not less than fifteen (15)
days written notice to Lender, up to the aggregate principal amount of
$10,000,000 (the "Line of Credit Loan"), in increments at the discretion of
Lender. Lender's obligation to make any advance to Borrower under the Loan and
the Note shall automatically suspend upon any earlier occurrence of an Event of
Default unless and until waived by Lender in writing. Lender may, in its sole
discretion, refuse to make advances or readvances for any reason whatsoever.

         3.   BORROWER'S REPRESENTATIONS AND WARRANTIES. Borrower represents and
warrants to Lender, all of which representations and warranties shall be
continuing until the Loan is fully paid and Borrower's obligations under this
Agreement and the Related Documents are fully performed, as follows:

              A. Borrower's Existence and Authority. Borrower is a Michigan
         corporation, the person executing this Agreement has full power and
         complete authority to execute this Agreement and all Related Documents,
         and this Agreement and the Related Documents are valid, binding and
         enforceable against Borrower.

              B. Financial Information. All financial information provided to
         Lender has been prepared and will continue to be prepared in accordance
         with generally accepted accounting principles ("GAAP"), consistently
         applied, and fully and fairly presents the financial condition of
         Borrower as of the date or for the operating period thereof. There has
         been no material adverse change in Borrower's business, property, or
         financial condition since the date of Borrower's latest Financial
         Statements provided to Lender.


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              C. No Litigation/No Misrepresentations. There are no civil or
         criminal proceedings pending before any court, government agency,
         arbitration panel, or administrative tribunal or, to Borrower's
         knowledge, threatened against Borrower, which may result in any
         material adverse change in the business, property, or financial
         condition of Borrower. All representations and warranties in this
         Agreement and the Related Documents are true and correct and no
         material fact has been omitted.

         4.   AFFIRMATIVE COVENANTS. As of the date of this Agreement and
continuing until all of Borrower's obligations under this Agreement and the
Related Documents are fully performed and until the Loan is fully repaid to
Lender, Borrower shall at all times comply with the following covenants:

              A. Notice of Adverse Events. Borrower shall promptly notify Lender
         in writing of any litigation, indictment, governmental proceeding,
         default, or any other occurrence which may have a material adverse
         effect on Borrower's business, property or financial condition.

              B. Maintain Business Existence and Operations. Borrower shall do
         all things necessary to keep in full force and effect Borrower's
         corporate existence and continue its business as presently conducted.

              C. General Compliance with Law. Borrower shall at all times
         operate its business in strict compliance with all applicable Federal,
         State, and local laws, ordinances and regulations, and refrain from
         engaging in any civil or criminal activity proscribed by Federal, State
         or local law.

         5.   EVENTS OF DEFAULT. The occurrence of any of the following events
shall constitute an Event of Default under this Agreement:

              A. Failure to Pay Amounts Due. Any principal or interest under the
         Note is not paid when due.

              B. Insecurity. Lender deems itself insecure believing that the
         prospect of payment of the Loan is impaired.

              C. Misrepresentations; False Financial Information. Any statement,
         warranty or representation of Borrower in connection with or contained
         in this Agreement, the Related Documents, or any Financial Statements
         now or hereafter furnished to Lender by or on behalf of Borrower, is
         false or misleading.

              D. Noncompliance with Loan Agreements. Borrower breaches any
         covenant, term, condition or agreement stated in this Agreement or the
         Related Documents.

              E. Cessation/Termination of Existence. Borrower shall cease doing
         business or Borrower's existence is terminated by sale, dissolution,
         merger or otherwise.

              F. Bankruptcy or Receivership. Any conveyance is made of
         substantially all of Borrower's assets, any assignment is made for the
         benefit of creditors, any receiver is appointed, or any insolvency,
         liquidation or reorganization proceeding under the Bankruptcy Code or
         otherwise shall be filed by or against Borrower.

              G. Attachments; Tax Liens. Any attachment, execution, levy,
         forfeiture, tax lien or similar writ or process is issued against any
         property of Borrower.

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              H. Material Adverse Change. Any material adverse change occurs or
         is imminent the effect of which would be to substantially diminish
         Borrower's financial condition, business, or the ability to perform its
         agreements with Lender.

              I. Other Lender Default. Any other indebtedness to Lender or any
         other creditor (including, without limitation, Financial Institutions
         (as defined below)) becomes due and remains unpaid after acceleration
         of the maturity or after the stated maturity.

         6.   REMEDIES ON DEFAULT.

              A. Acceleration Set-Off. Upon the occurrence of any Event of
         Default, Lender may, at Lender's option, declare the Loan to be
         immediately due and payable. The foregoing shall not in any way impair
         Lender's right to demand repayment under the terms of the Note.

              B. Remedies; No Waiver. The remedies provided in this Agreement
         are cumulative and not exclusive, and Lender may exercise any remedies
         available to it at law, in equity, and as are provided in this
         Agreement, and any other written agreement between Borrower and Lender.
         No delay or failure of Lender in exercising any right, remedy, power,
         or privilege under this Agreement or the Related Documents shall affect
         that right, remedy, power or privilege, nor shall any single or partial
         exercise preclude the exercise of any other right, remedy, power or
         privilege. No delay or failure of Lender to demand strict adherence to
         the terms of this Agreement or the Related Documents shall be deemed to
         constitute a course of conduct inconsistent with Lender's right at any
         time, before or after any Event of Default, to prospectively demand
         strict adherence to the terms of this Agreement and the Related
         Documents.

         7.   MISCELLANEOUS.

              A. Compliance with Lender Agreements. Borrower acknowledges that
         Borrower has read and understands this Agreement, the Related
         Documents, and all other written agreements between Borrower and
         Lender, and Borrower agrees to fully comply with all of the agreements.

              B. Further Action. Borrower agrees, from time to time, upon
         Lender's request to make, execute, acknowledge, and deliver to Lender,
         such further and additional instruments, documents, and agreements, and
         to take such further action as may be required to carry out the intent
         and purpose of this Agreement and prompt repayment of the Loan.

              C. Governing Law/Partial Illegality. This Agreement and the
         Related Documents shall be interpreted and the rights of the parties
         determined under the laws of the State of Michigan. Should any part,
         term, or provision of this Agreement be adjudged illegal or in conflict
         with any law of the United States of America or State of Michigan, the
         validity of the remaining portion or provisions of the Agreement shall
         not be affected.

              D. Writings Constitute Entire Agreement; Modifications Only in
         Writing. This Agreement together with all other written agreements
         between Borrower and Lender, including, without limitation, the Related
         Documents, constitute the entire agreement of the parties and there are
         no other agreements, express or implied. None of the parties shall be
         bound by anything not expressed in writing, and neither this Agreement
         nor the Related Documents can be modified except by a writing executed
         by Borrower and by Lender. This Agreement shall inure to the benefit of
         and shall be

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         binding upon all of the parties to this Agreement and their respective
         successors and assigns; provided however, that Borrower cannot assign
         or transfer its rights or obligations under this Agreement without
         Lender's prior written consent.

              E. Headings. All section and paragraph headings in this Agreement
         are included for reference only and do not constitute a part of this
         Agreement.

              F. Term of Agreement. This Agreement shall continue in full force
         and effect until all of Borrower's obligations to Lender are fully
         satisfied and the Loan is fully repaid.

         8.   DEFINITIONS. The following words shall have the following meanings
in this Agreement:

              A. "Event of Default" shall mean any of the events described in
         Section 5 of this Agreement or in the Related Documents.

              B. "Financial Institution" shall mean any bank as defined in
         section 3(a)(2) of the Securities Act of 1933, as amended (the "Act"),
         savings and loan association or other institution as defined in section
         3(a)(5) (A) of the Act, insurance company as defined in section 2(13)
         of the Act, or investment banking firm.

              C. "Financial Statements" shall mean all balance sheets, income
         statements, and other financial information which have been, are now,
         or in the future are furnished to Lender.

              D. "LIBOR" shall mean the rate as quoted by the Dow Jones Telerate
         System "LIBO Page" report of such interest rates as determined by
         Reuter's News Service.

              E. "Note" shall mean that certain $10,000,000 demand promissory
         note from Borrower to Lender, in the form attached hereto as Exhibit A.

              F. "Related Documents" shall mean any and all documents,
         promissory notes, and agreements executed in connection with this
         Agreement. The term shall include documents existing before, at the
         time of execution of, and documents executed concurrent with or after
         the date of, this Agreement.

             [The remainder of this page intentionally left blank.]

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         IN WITNESS WHEREOF, the parties have executed this Loan Agreement as of
the date first written above.



                                  BORROWER:

                                  BINGHAM FINANCIAL SERVICES CORPORATION, a
                                  Michigan corporation


                                  By:
                                      ------------------------------------------
                                        Ronald A. Klein
                                  Its:  Chief Executive Officer


                                  LENDER:

                                  SUN COMMUNITIES OPERATING LIMITED PARTNERSHIP,
                                  a Michigan limited partnership


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


                                  By:
                                      ------------------------------------------
                                        Gary A. Shiffman
                                  Its:  President



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