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                               GUARANTY AGREEMENT

        THIS GUARANTY AGREEMENT is made by BEHRINGER HARVARD REIT I, INC. (the
"GUARANTOR") to and for the benefit of FIRST AMERICAN BANK, SSB, a Texas state
savings bank (the "LENDER"), its successors and assigns and any subsequent
holder or holders of the Note (hereinafter defined).

                                R E C I T A L S :

        A.      Behringer Harvard Holdings, LLC (the "BORROWER"), desires to
borrow from the Lender from time to time a principal sum not in excess of
$12,600,000.00 (the "LOAN"), pursuant to that certain Loan Agreement (the "LOAN
AGREEMENT") and related Promissory Note (the "NOTE") of even date herewith,
between the Borrower and the Lender.

        B.      The Guarantor desires the Lender to make the Loan to the
Borrower, and the Lender requires, as a condition thereof, that the Guarantor
execute and deliver to the Lender this Guaranty Agreement and that certain
Security Agreement (the "SECURITY AGREEMENT") of even date herewith, pledging
certain collateral to secure the Loan.

        C.      Guarantor will receive, directly or indirectly, a tangible
benefit from the disbursement of the proceeds of the Loan by the Lender to the
Borrower.

        NOW, THEREFORE, in consideration of the premises and to induce the
Lender to make the Loan, and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Guarantor
unconditionally guarantees to the Lender the prompt and full payment of the
Guaranteed Indebtedness (hereinafter defined) as and when the Guaranteed
Indebtedness shall become due and payable, whether by lapse of time,
acceleration of maturity or otherwise, and at all times thereafter. As used
herein the term "GUARANTEED INDEBTEDNESS" means: (i) the principal of and
accrued interest on the Note; (ii) any and all costs, attorneys' fees and
expenses incurred by the Lender by reason of Borrower's default in the payment
of the Note or default in the performance of any conditions or obligations under
any of the other Loan Documents (hereinafter defined); and (iii) any and all
additional amounts owing or which hereafter become owing by the Borrower under
the terms of the Note, the Loan Agreement, the Security Agreement, and/or any
other instrument evidencing, securing or governing the disbursement of the Loan,
whether presently existing or hereinafter entered into (collectively, the "LOAN
DOCUMENTS"). The Guarantor further unconditionally guarantees to the Lender the
prompt observance and performance of all covenants and agreements of the
Borrower contained in the Loan Documents.

        The obligations of the Guarantor shall be performable without demand of
the Lender and shall be unconditional irrespective of the genuineness, validity,
regularity or enforceability of the

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Loan Documents or any other circumstance which might otherwise constitute a
legal or equitable discharge of a surety or a guarantor. The Guarantor waives
diligence, presentment, demand of payment, protest, all notices (whether of
nonpayment, acceleration, intent to accelerate, dishonor, protest or otherwise)
with respect to the Note, notice of acceptance of this Guaranty Agreement and of
the incurring by the Borrower of any of the obligations hereinbefore mentioned
and all demands whatsoever. The Guarantor further waives all rights to require
the Lender to: (i) proceed against the Borrower; (ii) proceed against or exhaust
any collateral held by the Lender to secure the payment of the Guaranteed
Indebtedness; or (iii) pursue any other remedy the Lender may now or hereafter
have against the Borrower.

        The Guarantor agrees that, at any time or from time to time, without
notice to the Guarantor and without affecting the liability of the Guarantor:
(i) the time for payment of the principal of or interest on the Note may be
extended, or the Note may be renewed in whole or in part; (ii) the time for the
Borrower's performance of or compliance with any covenant or agreement contained
in the Loan Documents may be extended, or such performance or compliance may be
waived; (iii) the maturity of the Note may be accelerated as provided therein or
in the Loan Documents; (iv) the Loan Documents may be modified or amended by the
Lender and the Borrower in any respect; and (v) any security for the Loan may be
modified, exchanged, surrendered or otherwise dealt with and/or additional
security may be pledged or mortgaged for the Loan.

        Guarantor agrees that Guarantor's obligations under this Guaranty
Agreement shall not be released, diminished, impaired, reduced or affected by
the occurrence of any one or more of the following events: (i) the taking or
accepting of any other security or guaranty for any or all of the Guaranteed
Indebtedness; (ii) any release, surrender, exchange, subordination or loss of
any security at any time existing or in connection with any or all of the
Guaranteed Indebtedness; (iii) any partial release of the liability of Guarantor
hereunder; (iv) the death, insolvency, bankruptcy, disability, dissolution,
liquidation, termination, receivership, reorganization or lack of corporate,
partnership or other power of the Borrower, any other guarantor of the
Guaranteed Indebtedness, or any party at any time liable for the payment of any
or all of the Guaranteed Indebtedness, whether now existing or hereafter
occurring; (v) any neglect, delay, omission, failure or refusal of Lender to
take or prosecute any action for the collection of any of the Guaranteed
Indebtedness or to foreclose or take or prosecute any action under the Loan
Documents; (vi) the unenforceability of all or any part of the Guaranteed
Indebtedness against Borrower, whether because the Guaranteed Indebtedness
exceeds the amount permitted by law, the act of creating the Guaranteed
Indebtedness, or any part thereof, is ULTRA VIRES, the officer or persons
creating the Guaranteed Indebtedness acted in excess of their authority, or
otherwise, it being agreed that Guarantor shall remain liable hereon regardless
of whether Borrower or any other person is found to be not liable on the
Guaranteed Indebtedness, or any part thereof, for any reason; or (vii) if any
payment by Borrower to Lender is held to constitute a preference under the
bankruptcy laws or if for any other reason Lender is required to refund such
payment or pay such payment to someone else. It is the intent of Guarantor and
Lender that the obligations and

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liabilities of Guarantor hereunder are absolute and unconditional under any and
all circumstances and that until the Guaranteed Indebtedness is fully and
finally paid, such obligations and liabilities shall not be discharged or
released, in whole or in part, by any act or occurrence which might, but for the
provisions of this Guaranty Agreement, be deemed a legal or equitable discharge
or release of a guarantor.

        The obligations secured under this Guaranty are limited to the principal
amount of funds borrowed by Borrower for each real estate project for tenant in
common syndications as specified in Section 4.06 of the Loan Agreement (each a
"PROJECT") and related accrued interest thereon. Borrower's certification that
the funds borrowed by Borrower are for a specific Project shall be dispositive
of that fact.

        The obligations of the Guarantor and any other guarantor of the
Guaranteed Indebtedness shall be joint and several. The Guarantor agrees that
the Lender, in its discretion, may: (i) bring suit against the Guarantor and any
other guarantor of the Guaranteed Indebtedness jointly and severally or against
any one or more of them; (ii) compound or settle with any one or more of the
guarantors of the Guaranteed Indebtedness for such consideration as the Lender
may deem proper; (iii) release one or more of the guarantors of the Guaranteed
Indebtedness from liability; and (iv) otherwise deal with the Guarantor and any
other guarantors of the Guaranteed Indebtedness in any manner whatsoever, and
that no such action shall impair the rights of the Lender to collect the
Guaranteed Indebtedness from the Guarantor.

        The Lender may assign its rights hereunder in whole or in part. Upon any
such assignment, all the terms and provisions of this Guaranty Agreement shall
inure to the benefit of such assignee to the extent so assigned. The terms used
to designate any of the parties herein shall be deemed to include the heirs,
legal representatives, successors and assigns of such parties, and the term
"LENDER" shall include, in addition to the Lender, any and all lawful owners,
holders or pledgees of all or any part of the Guaranteed Indebtedness.

        If, for any reason whatsoever, Borrower is now or hereafter becomes
indebted to Guarantor, such indebtedness and all interest thereon shall at all
times be subordinate in all respects to the Guaranteed Indebtedness, and
Guarantor shall not be entitled to enforce or receive payment thereof until the
Guaranteed Indebtedness has been paid in full. Guarantor waives and releases any
right the Guarantor may have: (i) of subrogation in or under any of the Loan
Documents; (ii) to participate in any way in any payments made by any party to
the Lender in connection with the Guaranteed Indebtedness; and (iii) in any
mortgaged property or any collateral given to secure the payment of the
Guaranteed Indebtedness.

        The Guarantor represents and warrants to the Lender that the financial
statements and information regarding the Guarantor which have been delivered to
the Lender are true and correct in all material respects, have been prepared in
accordance with generally accepted accounting practices applied on a consistent
basis throughout the period covered thereby, fairly

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present the financial position of the Guarantor as of the dates thereof and that
no material adverse change has occurred in the financial condition of the
Guarantor since the date of such financial statements.

        If Guarantor becomes liable for any indebtedness owing by the Borrower
to the Lender, by endorsement or otherwise, other than under this Guaranty
Agreement, such liability shall not in any manner be impaired or affected by
this Guaranty Agreement, and any rights of the Lender under the Guaranty
Agreement shall be cumulative of any and all other rights that the Lender may
ever have against the Guarantor.

        If any provision of this Guaranty Agreement or the application thereof
to any person or circumstance shall, for any reason and to any extent, be
invalid or unenforceable, neither the remainder of this Guaranty Agreement nor
the application of such provision to any other person or circumstance shall be
affected thereby, but rather the same shall be enforced to the greatest extent
permitted by law.

        The Guarantor shall pay all costs and expenses, including attorneys'
fees, which may be incurred by the Lender in the enforcement of this Guaranty
Agreement.

        This Guaranty Agreement and all rights, obligations and liabilities
arising hereunder shall be construed according to the laws of the State of
Texas. The Guarantor agrees that this Guaranty Agreement is performable in
Dallas County, Texas.

        EXECUTED as of the ____ day of October, 2004.


                                             GUARANTOR:

                                             BEHRINGER HARVARD REIT I, INC.


                                             By:________________________________
                                             Name:______________________________
                                             Title:_____________________________