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                                      Exhibit 99.2  First Amendment to Purchase
                                                    and Sale Agreement
                                                    between UM and the Trust
            
                 FIRST AMENDMENT TO PURCHASE AND SALE AGREEMENT

         This First Amendment made this 30th day of May, 1996, by and between UM
REAL ESTATE INVESTMENT COMPANY, LLC ("Seller") and BRANDYWINE REALTY TRUST
("Buyer").

                                   Background

         Seller and Buyer are parties to that certain Purchase and Sale
Agreement made as of the 28th day of March, 1996 (the "Agreement") with respect
to the sale of property known as Block 176.01, Lots 1, 2 and 3 on the official
tax map of the Township of Cherry Hill together with all improvements thereon
(the "Property").

         Buyer has requested that Seller extend the Closing Date and, to the
extent provided herein, the Due Diligence Period, and Seller has agreed to do so
pursuant to the terms and conditions hereafter set forth.

         NOW, THEREFORE, Buyer and Seller, for and in consideration of the
mutual covenants contained herein and other good and valuable consideration, the
receipt of which is hereby acknowledged, intending to be legally bound, do
hereby agree that notwithstanding anything to the contrary contained in the
Agreement:

         1. Definitions. All defined terms herein shall have the meaning
ascribed to them under the Agreement unless specifically provided herein to the
contrary.

         2. Deposit. (a) Article 2.1(a) is amended by adding thereto the
         following:

         In the event Closing does not occur by June 14, 1996, unless due to a
         default by Seller or due to Buyer's termination of the Agreement as
         permitted under Article 3 of this First Amendment, the Title Company
         shall continue to hold the Ninety Thousand Dollars ($90,000) held as
         Deposit, such sum to become non-refundable on June 14, 1996 and Buyer
         shall concurrently pay to the Title Company by June 14, 1996 by
         certified check, bank check or wire transfer, an additional One Hundred
         Fifty Thousand Dollars ($150,000) which shall become part of the
         Deposit and thereupon, the Deposit shall be non-refundable. Buyer's
         failure to pay such additional $150,000 by the above time period to
         Seller shall constitute a default under the Agreement. Until 5 p.m. on
         June 14, 1996, only $10,000 of the Deposit pursuant to subparagraph (b)
         below shall be non-refundable; thereafter, unless Seller defaults
         hereunder, the remaining Two Hundred Forty Thousand Dollars ($240,000)
         shall become non-refundable.

           (b) Ten Thousand Dollars ($10,000) of the Deposit currently held by
         the Title Company shall be deemed non-refundable as of this date and
         shall be immediately paid by the Title Company to Seller. Seller shall
         be entitled to

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         retain such amount in the event Closing does not occur for any reason
         (including Buyer's termination of the Agreement as permitted under the
         Agreement or this First Amendment) unless Seller defaults under the
         Agreement, in which event Seller shall reimburse such $10,000 to Buyer.
         In the event Buyer terminates the Agreement as permitted under Article
         3 of this First Amendment, the remaining Ninety Thousand Dollars
         ($90,000) of the Deposit shall be returned by the Title Company to
         Buyer if such date is on or before June 14, 1996; however, if Seller
         defaults prior to Closing, the entire Deposit, including the additional
         $150,000 and interest shall be returned to Buyer.

         3. Due Diligence. Article 3 of the Agreement is amended by adding
thereto the following:

         Buyer acknowledges that it has completed all of the investigations
         which it is entitled to undertake pursuant to Article 3 of the
         Agreement with the exception of those specific items set forth on
         Schedule 1 attached hereto and made a part hereof (the "Remaining Due
         Diligence Items"). Buyer shall, from and after the date hereof, no
         longer have the right to terminate the Agreement for any reason other
         than (i) Buyer's good faith determination not to proceed based on the
         results of one or more of the Remaining Due Diligence Items or (ii)
         Buyer's good faith determination that it is unable to obtain
         satisfactory financing to acquire the Property. The $50,000 addition to
         the Deposit required under Article 2.1(a) of the Agreement must be paid
         by Buyer to the Title Company by 5 p.m. E.D.S.T. on May 30, 1996
         notwithstanding the failure of Buyer to have completed the Remaining
         Due Diligence Items. Such additional $50,000 shall be governed by the
         terms of amended Article 2.1. Buyer shall have the right to terminate
         this Agreement solely as a result of Buyer's good faith determination
         that is not satisfied with the result of one or more of the Remaining
         Due Diligence Items or Buyer's good faith determination that it is
         unable to obtain satisfactory financing to acquire the Property, by
         notice to Seller not later than 5 p.m. on June 14, 1996 following which
         (provided Buyer is not then in default hereunder), the Title Company
         shall return the remaining $90,000 of the Deposit to Buyer and
         thereafter neither party shall have any further rights or obligations
         under the Agreement, except for those which by their terms survive
         termination of the Agreement. If Buyer does not terminate the Agreement
         as permitted under this Article 3 of this First Amendment, the entire
         Deposit (e.g., $250,000) shall become non-refundable so long as Seller
         does not default hereunder.

         4. Closing. Article 4 of the Agreement shall be amended to provide that
Closing shall be held on or before July 19, 1996, at the time and place set
forth in the Agreement.

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         5. Signatures. This First Amendment may be executed in one or more
counterparts, each of which shall be deemed an original and part of one and the
same document. Telefax signatures shall be deemed the equivalent of original
signatures.

         Except to the extent specifically set forth herein, the terms and
conditions of the Agreement are hereby ratified and confirmed. In the event of
any conflict between the terms of the Agreement and the terms of this First
Amendment, the terms of this First Amendment shall prevail.

         IN WITNESS WHEREOF, the parties hereto have set forth their hands and
seals the day and year first above written.

                              SELLER:

                              UM REAL ESTATE INVESTMENT
                              COMPANY, LLC, a New Jersey limited liability
                              company

                              By: 
                                 ------------------------------------------
                                  Arthur W. Hicks, Jr., Manager

                              BUYER:

                              BRANDYWINE REALTY TRUST, a Maryland
                              real estate investment trust

                              By: XXXXXXXXXXX
                                 ------------------------------------------


50524-3
May 30, 1996

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                                   Schedule 1

                          Remaining Due Diligence Items

         1. Identification of water pressure problem and cause of the sink hole
on the Property. Remedy and cost allocation satisfactory to Buyer.

         2. Finalization and approval of survey by Buyer.

         3. Review and approval of ISRA non-applicability letter (Seller to
deliver per Article 15.1 of the Agreement).

         4. Review and approval of ISRA No-Further Action Letter regarding the
U.S.T. previously located on the Property.

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