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                                                                   EXHIBIT 10.35

                    ASSIGNMENT OF PURCHASE AND SALE AGREEMENT

         This Assignment of Purchase and Sale Agreement (this "ASSIGNMENT") is
made as of July ___, 2004, by Realty America Group (4245 Central), LP, a Texas
limited partnership ("ASSIGNOR"), and Behringer Harvard 4245 CENTRAL LP, a Texas
limited partnership ( "ASSIGNEE").

                                   BACKGROUND

         A. Assignor, as purchaser, entered into that certain Contract of Sale
dated effective as of April 19, 2004 (as same may have been amended, the
"AGREEMENT") with Vortisch Holdings, L.P., a Texas limited partnership, as
seller, in respect of an office building commonly known as 4245 Central
Expressway in the City of Dallas, Dallas 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 $100,000 as Earnest
Money (as defined in the Agreement) under the Agreement and has incurred the
amount of $25,000 ("PURSUIT COSTS") in pursuit costs in respect of the Property.
Concurrently with the execution of this Assignment, Assignee shall cause
Behringer Harvard Short-Term Opportunity Fund I LP, a Texas limited partnership
("BH SHORT TERM"), to pay to Assignor the amount of $62,500 to be applied as
follows: (a) the amount of $12,500 shall reimburse Assignor for fifty percent
(50%) of the Pursuit Costs (it being agreed that Assignor shall bear the
remaining fifty percent (50%) of such Pursuit Costs); and (b) the amount of
$50,000 shall reimburse Assignor for fifty percent (50%) of the Earnest Money
deposited by Assignor. Upon such payment by Assignor, the Earnest Money shall be
deemed apportioned such that fifty percent (50%) thereof belongs to Assignor and
the remaining fifty percent (50%) thereof belongs to BH Short Term. In the event
that additional Earnest Money is required to be deposited under the Agreement,
Assignee shall cause BH Short Term to deposit same.

         3. CAPITAL CONTRIBUTIONS. 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 Pursuit Costs and Earnest Money belonging to Assignor ($62,500)
shall be credited towards the contribution required to be made by Assignor under
the Partnership Agreement, and the portion of the Pursuit Costs and Earnest
Money belonging to BH Short Term ($62,500 plus any additional Earnest Money
deposited by BH Short Term) shall be credited towards the contribution required
to be made by BH Short Term under the Partnership Agreement.

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

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                  (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 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
         Section 12 of 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.


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

                                     ASSIGNOR:

                                     REALTY AMERICA GROUP (4245
                                     CENTRAL), LP, a Texas limited partnership

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

                                           By:   /s/ Webb M. Sowden, III
                                              ----------------------------------
                                           Name:  Webb M. Sowden, III
                                           Title:  Member




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                                     ASSIGNEE:

                                     BEHRINGER HARVARD 4245 CENTRAL LP,
                                     a Texas limited partnership

                                     By: Behringer Harvard 4245 Central GP, LLC,
                                         a Texas limited liability company
                                         Its General Partner

                                         By:
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                                         Name:
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                                         Title:
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