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                  ASSIGNMENT OF AGREEMENT OF SALE AND PURCHASE

        This Assignment of Agreement of Sale and Purchase (this "ASSIGNMENT") is
made as of July ___, 2004, by Realty America Group (1221 coit road), LP, a Texas
limited partnership ("ASSIGNOR"), and Behringer Harvard 1221 coit LP, a Texas
limited partnership ( "ASSIGNEE").

                                   BACKGROUND

        A.      Assignor, as purchaser, entered into that certain Agreement of
Sale and Purchase dated effective as of July 6, 2004 (as same may have been
amended, the "AGREEMENT") with 98 CUSA Plano, L.P., a Delaware limited
partnership, as seller, in respect of an office building commonly known as 1221
Coit Road in Collin County, Texas, as more particularly described in the
Agreement (the "PROPERTY").

        B.      Assignor desires to assign all of its interest in the Agreement
to Assignee and Assignee desires to accept the assignment.

                                    AGREEMENT

        1.      ASSIGNMENT. For good and valuable consideration paid to
Assignor, the receipt and sufficiency of which are hereby acknowledged, Assignor
does hereby ASSIGN AND TRANSFER to Assignee all of the right, title and interest
of Assignor in and to the Agreement. Assignor hereby accepts such assignment and
assumes and agrees to perform all obligations of Assignor as "Purchaser" under
the Agreement.

        2.      DEPOSIT. Assignor has deposited the amount of $25,000 as earnest
money under the Agreement. Upon the execution of this Assignment, Assignee shall
be obligated to cause Behringer Harvard Short-Term Opportunity Fund I LP, a
Texas limited partnership ("BH SHORT TERM"), to deposit the amount of $100,000
in additional earnest money as required by the Agreement. Assignor and BH Short
Term, among others, have executed (or will execute) that certain Agreement of
Limited Partnership of Assignee (the "PARTNERSHIP AGREEMENT"), pursuant to which
each of Assignor and BH Short Term is to contribute certain funds necessary to
acquire the Property. Upon the closing of the transaction that is the subject of
the Agreement, the portion of the Earnest Money belonging to Assignor ($25,000)
shall be credited towards the contribution required to be made by Assignor under
the Partnership Agreement, and the portion of the Earnest Money belonging to BH
Short Term ($100,000) shall be credited towards the contribution required to be
made by BH Short Term under the Partnership Agreement. In the event that
additional earnest money is required to be deposited under the Agreement,
Assignee shall cause BH Short Term to deposit same.

        4.      REPRESENTATIONS. Assignor hereby unconditionally represents and
warrants to, and covenants with, Assignee as follows:

                (a)     The Agreement is in full force and effect. A true,
        correct and complete copy of the Agreement (including all amendments to
        the initial Agreement) is attached hereto as EXHIBIT A.

                (b)     Assignor is not currently in default under the
        Agreement, and, to Assignor's knowledge, no default by Seller exists
        under the Agreement.

                (c)     After the execution of this Assignment, Assignee shall
        have the sole right to exercise any right to terminate the Agreement.

                (d)     Neither Assignor nor any affiliate of Assignor is
        receiving any compensation in connection with the acquisition of the
        Property, other than such compensation as is reflected in

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        documents executed by Assignee or affiliates of Assignee. Without
        limiting the generality of the foregoing, Assignor represents and
        warrants to Assignee that neither Assignor nor any affiliate of Assignor
        has or will receive any commission or other payment from the seller
        named in the Agreement (or any affiliate of such seller) in connection
        with the sale of the Property to Assignee, except as expressly provided
        in the Agreement.

        5.      FURTHER ASSURANCES. Each party agrees that it will without
further consideration execute and deliver such other documents and take such
other action, whether prior or subsequent to Closing, as may be reasonably
requested by the other party to consummate more effectively the purposes or
subject matter of this Agreement.

        6.      ATTORNEYS' FEES. In the event of any controversy, claim or
dispute between the parties affecting or relating to the subject matter or
performance of this Agreement, the prevailing party shall be entitled to recover
from the non-prevailing party all of its reasonable expenses, including
reasonable attorneys' fees.

        7.      COUNTERPARTS. This Agreement may be executed in several
counterparts, and all such executed counterparts shall constitute the same
agreement. It shall be necessary to account for only one such counterpart in
proving this Agreement.

        8.      SEVERABILITY. If any provision of this Agreement is determined
by a court of competent jurisdiction to be invalid or unenforceable, the
remainder of this Agreement shall nonetheless remain in full force and effect.

        9.      APPLICABLE LAW. THIS AGREEMENT IS PERFORMABLE IN DALLAS COUNTY,
TEXAS, AND SHALL IN ALL RESPECTS BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE SUBSTANTIVE FEDERAL LAWS OF THE UNITED STATES AND THE LAWS OF THE
STATE OF TEXAS.

        10.     CAPTIONS. The section headings appearing in this Agreement are
for convenience of reference only and are not intended, to any extent and for
any purpose, to limit or define the text of any section or any subsection
hereof.

        11.     CONSTRUCTION. The parties acknowledge that the parties and their
counsel have reviewed and revised this Agreement and that the normal rule of
construction to the effect that any ambiguities are to be resolved against the
drafting party shall not be employed in the interpretation of this Agreement or
any exhibits or amendments hereto.

        EXECUTED to be effective as of the date first written above.




                      [This space intentionally left blank]

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                                   ASSIGNOR:

                                   REALTY AMERICA GROUP (1221 COIT ROAD),
                                   L.P., a Texas limited partnership

                                   By:  Realty America Group Investment, LLC,
                                        a Texas limited liability company
                                        Its General Partner


                                        By:_____________________________________
                                        Name:   Webb M. Sowden, III
                                        Title:  Member

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                                   ASSIGNEE:

                                   BEHRINGER HARVARD 1221 COIT LP,
                                   a Texas limited partnership

                                   By:  Behringer Harvard 1221 Coit GP, LLC,
                                        a Texas limited liability company
                                        Its General Partner


                                        By:_____________________________________
                                        Name:___________________________________
                                        Title:__________________________________