<PAGE>
                                                                    EXHIBIT 10.3


             REINSTATEMENT AND SECOND AMENDMENT TO AGREEMENT OF SALE

      REINSTATEMENT AND SECOND AMENDMENT TO AGREEMENT OF SALE (this "Second
Amendment"), dated as of March 11, 2003, between INTERSTATE 78 OFFICE PARK,
LTD., a New Jersey limited partnership, NEW YORK DISTRIBUTION CENTER, L.P., a
New Jersey limited partnership, RARITAN BUILDING ASSOCIATES LIMITED PARTNERSHIP,
a New Jersey limited partnership, 191 TALMADGE ROAD REALTY HOLDINGS, L.P., a New
Jersey limited partnership, CARLSTADT BUILDING REALTY HOLDINGS, L.P., a New
Jersey limited partnership, CARLSTADT ASSOCIATES, LTD., a New Jersey limited
partnership, APOLLO ASSOCIATES, LTD., a New Jersey limited partnership, EASTMANS
ROAD ASSOCIATES, LTD., a New Jersey limited partnership, WEBRO ASSOCIATES, LTD.,
a New Jersey limited partnership and OAKLAND BUILDING ASSOCIATES, LTD., a New
Jersey limited partnership (each such party being herein called a "Seller" and
all such parties being herein collectively called the "Sellers") and KEYSTONE
NEW JERSEY ASSOCIATES, LLC, a Delaware limited liability company ("Purchaser").

                              PRELIMINARY STATEMENT

      Sellers and Purchaser entered into an Agreement of Sale dated March 1,
2002, as amended by various letter amendments extending the Due Diligence Period
to the last expiration date of August 5, 2002 (the "Agreement of Sale") and by
Reinstatement and First Amendment to Agreement of Sale dated August 28, 2002
(the "First Amendment") (the Agreement of Sale, as amended by such letter
agreements and the First Amendment being herein called the "Original
Agreement"), pursuant to which Sellers agreed to sell and convey to Purchaser,
and Purchaser agreed to acquire from Sellers, subject to the terms and
conditions of the Original Agreement, certain Properties more specifically
described therein. Unless otherwise defined herein, all capitalized terms used
herein shall have the meaning specified in the Original Agreement. On September
30, 2002, Sellers terminated the Original Agreement pursuant to Section 14 of
the First Amendment.

      Except with respect to the properties known as 1200 Valley Brook Road,
Lyndhurst, New Jersey, and 3-5 Finderne Avenue, Bridgewater, New Jersey, Sellers
and Purchaser now desire to reinstate the Original Agreement and simultaneously
with this reinstatement to amend the Original Agreement, inter alia, to


                                      -5-
<PAGE>

(a) add as additional Sellers, 191 Talmadge Road Realty Holdings, L.P., Apollo
Associates, Ltd., Eastmans Road Associates, Ltd., Webro Associates, Ltd., and
Oakland Building Associates, Ltd., (b) add as additional properties to be
conveyed to Purchaser the five (5) properties owned by each such entity
described on Exhibit A-1 annexed hereto and (c) to otherwise modify and amend
the Original Agreement in the manner herein provided.

      NOW, THEREFORE, for and in consideration of the mutual covenants contained
herein, and other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, and intending to be legally bound, the parties
hereto agree as follows:

      1. Reinstatement of Original Agreement. Sellers and Purchaser hereby agree
that, effective upon the execution and delivery of this Second Amendment, the
Original Agreement, as amended hereby, is hereby reinstated as a valid and
binding agreement with respect to all of the Properties except 1200 Valley Brook
Road, Lyndhurst, New Jersey, and 3-5 Finderne Avenue, Bridgewater, New Jersey.

      2. Removal of 1200 Valley Brook Road and 3-5 Finderne Avenue, Bridgewater,
New Jersey. The parties hereby agree that the properties identified in the
Original Agreement as 1200 Valley Brook Road, Lyndhurst, New Jersey, and 3-5
Finderne Avenue, Bridgewater, New Jersey, are hereby removed from the Original
Agreement. The term "Properties" as used in the Original Agreement and this
Second Amendment shall be deemed not to include 1200 Valley Brook Road and 3-5
Finderne Avenue, and all references in the Original Agreement, including,
without limitation, the provisions of clause (c) of Section 2.5 of the Agreement
of Sale and all references to 1200 Valley Brook Road and 3-5 Finderne Avenue,
Bridgewater, New Jersey, in the Exhibits thereto are hereby deleted in their
entirety. The term "Sellers" as used in the Original Agreement and this Second
Amendment shall not include Fin Associates Limited Partnership or Wedgewood
Plaza, L.P. but shall include all other Sellers identified in the introductory
paragraph of this Second Amendment.

      3. Sale of Additional Properties. In addition to the Properties described
in the Original Agreement (subject to the deletion of 1200 Valley Brook Road and
3-5 Finderne Avenue), Sellers hereby agree to sell, convey, transfer and assign
to Purchaser, and Purchaser hereby agrees to purchase and acquire from Sellers,
the additional Properties identified on Exhibit A-1


                                      -2-
<PAGE>

annexed hereto (the "Additional Properties") upon the terms and conditions
contained in the Original Agreement as amended and modified hereby. The parties
acknowledge that although the Property known as 191 Talmadge Road was deleted
from the transaction pursuant to Paragraph 2 of the First Amendment, such
property is now included in this transaction. The conveyance of all Properties
shall include all right title and interest of the respective Sellers in and to
(a) all licenses, permits and other authorizations for the use, operation,
maintenance, ownership and development of the Additional Properties, (b) all
plans, specifications, shop drawings, operating manuals and other technical data
relating to the Improvements and the Personal Property, (c) all software and
security codes relating to the operation of the Improvements and the Personal
Property and (e) all rights under Guarantees and Warranties. The term
"Properties" as used in the Original Agreement, as modified hereby, shall be
deemed to include the Additional Properties.

      4. Legal Descriptions. Exhibit A to the Agreement of Sale is hereby
deleted in its entirety and Exhibit A-1 annexed hereto is hereby substituted
therefor, it being agreed that Exhibit A-1 contains the legal descriptions of
all of the Properties based upon current surveys. The parties agree that the
deeds for the Properties shall contain both the legal descriptions contained in
Exhibit A-1 and the legal descriptions contained in the deeds vesting title in
the Sellers.

      5. Termination Limitation. The term "Termination Limitation" is hereby
deleted from the Original Agreement. The parties acknowledge that,
notwithstanding the provisions of Sections 8.1, 8.2 or 8.3 of the Original
Agreement, in the event Purchaser elects to terminate the Original Agreement as
amended by this Second Amendment with respect to any Property, it must terminate
the Original Agreement as amended by this Second Amendment with respect to all
Properties, whereupon the Deposit shall be refunded to Purchaser, whereupon
neither Sellers nor Purchaser shall have any further rights against the other
thereunder.

      6. Purchase Price. Section 2.2 of the Original Agreement is hereby amended
to provide that the aggregate Purchase Price for the Properties is Eighty Five
Million Three Hundred Fifty Thousand Dollars ($85,350,000.00). The entire
Purchase Price shall be payable on the Closing Date. The Allocable Purchase
Price for each of the Properties is shown on Exhibit C-1 annexed hereto.


                                      -3-
<PAGE>

      7. Deletion of Certain Provisions from Agreement of Sale and First
Amendment. The provisions of Sections 2.3, 2.4, 2.5, 2.6(a), (b), (e) and (f),
Section 9.2 (f) and Section 9.4(l) of the Agreement of Sale are hereby deleted
in their entirety. Paragraph 14 of the First Amendment is hereby deleted in
entirety.

      8. Adjustments to Purchase Price. The first sentence of clause (a) of
Section 3 of the First Amendment is hereby deleted. The adjustment to the
Purchase Price specified in clause (b) of Section 3 of the First Amendment is
hereby deleted in its entirety.

      9. Escrows. (a) Except as provided herein, all escrows specified in the
Original Agreement shall remain in full force and effect. Paragraph 4 of the
First Amendment is deleted in its entirety and clause (c) below is substituted
therefor. In addition, the following additional escrows shall be established at
the closing:

            (a) The number "$456,000" appearing in clause (c) of Section 2.6 is
            deleted and the number "$158,175" is hereby substituted therefor.
            The parties acknowledge that a portion of the space previously
            occupied by Taylor Packaging consisting of approximately 62,700
            square feet has been leased to Midstate Motor. If all or any portion
            of the remaining 33,300 square feet of the Taylor Packaging Space is
            leased, the amount of monies to be released to Purchaser shall be
            reduced as provided in clause (c) of Section 2.6.

            (b) The parties acknowledge and agree that the escrow to be
            established pursuant to clause (d) of Section 2.6 of the Agreement
            of Sale shall be $155,880. The parties acknowledge that a portion of
            the GMR space has been leased to Answer Pal, Inc. for a term
            expiring October 9, 2003 with a right to extend for one year. In
            addition to Seller's rights under Section 2.6(d), if Purchaser
            collects rent due and payable under the Answer Pal, Inc. Lease, as
            the same may be amended by Purchaser and such tenant, the Escrow
            Agent shall release to Seller the sum of $5,000 per month for each
            month that such rent is paid through and including the extension
            period of the Answer Pal, Inc. Lease.


                                      -4-
<PAGE>

            (c) The parties acknowledge that Cargo Logistics, the tenant leasing
            the Property commonly known as 200 Middlesex Avenue, Carteret, has
            filed for bankruptcy and there are arrearages of rent. With respect
            to such Property, on the Closing Date there shall be withheld from
            the Allocable Purchase Price for such Property and deposited with
            the Escrow Agent the sum of $100,000, as security for rent and
            operating expenses payable by Cargo Logistics for a six (6) month
            period following the Closing Date. Purchaser shall have the right,
            commencing on the corresponding day of the month immediately
            succeeding the Closing Date and continuing on the same day of each
            succeeding month for a total period of eight (8) consecutive months,
            to draw from such escrow account any rent not paid by Cargo
            Logistics within sixty (60) calendar days after its due date, until
            eight (8) months shall have expired after the Closing Date. If any
            monies remain in such escrow account at the expiration of such eight
            (8) month period, the applicable Seller shall be entitled to receive
            such monies.

            (d) The parties acknowledge that Extreme Fitness is negotiating to
            lease an additional 8,960 square feet of space at the Property known
            as 191 Talmadge Road (the "Expansion Space Lease"). If an Expansion
            Space Lease in the form of the Lease attached hereto as Exhibit DD
            is not executed by Extreme Fitness and delivered to Purchaser prior
            to the Closing Date, there shall be withheld from the Allocable
            Purchase Price for such Property and paid to Escrow Agent the sum of
            $200,000. Purchaser acknowledges that such Expansion Space Lease
            shall include tenant fit up not to exceed $117,000 and that a
            brokerage commission not to exceed five percent (5%) of the base
            rent will be payable in connection therewith, and that Purchaser
            shall be liable for such tenant fit up cost and brokerage
            commission. For each calendar month after the Closing Date for which
            the Expansion Space Lease is not executed by Extreme Fitness and
            delivered to Purchaser, the Escrow Agent shall release to Purchaser
            the sum of $10,250 (pro-rated for any portion of a month). The
            balance of such escrow shall be released to the applicable Seller at
            such time as such Expansion Space Lease is executed by Extreme
            Fitness and delivered to Purchaser. If the Expansion Space Lease is
            not executed by Extreme Fitness and delivered


                                      -5-
<PAGE>

            to Purchaser within 120 calendar days after the Closing Date, such
            monies shall be paid to Purchaser.

      10. Lucent Rent. The parties acknowledge that Lucent has vacated space at
the Property known as 121 Fieldcrest Avenue and is not paying any rent.
Purchaser hereby assigns to the applicable Seller, effective as of the Closing
Date, the right to all rents due from Lucent prior to the closing and the right
to collect rent for a period of three (3) months after the Closing Date.

      11. Deposit Monies. Paragraph 5 of the First Amendment is hereby deleted
in its entirety and the following provision are hereby substituted therefor:

            ""The Purchase Price, plus or minus any net closing adjustments,
            shall be pied by wire transfer or trust account check of the Escrow
            Agent on the Closing Date. All references in the Original Agreement
            to the "Deposit are hereby deleted."

All references in the Original Agreement to the term "Deposit" are deleted.

      12. Escrow. Section 2.8 of the Original Agreement shall be applicable to
all escrows to be established at the closing pursuant to the provisions of the
Original Agreement and this Second Amendment.

      13. Due Diligence. Purchaser acknowledges that is has completed its due
diligence investigations of the Properties and is satisfied with the results
thereof. Purchaser hereby waives the right to terminate the Original Agreement
pursuant to Section 4.1 of the Original Agreement and Paragraph 7 of the First
Amendment.

      14. Brokerage Obligations. Section 4.6 of the Agreement of Sale is hereby
supplemented to include the following provision:

            "Notwithstanding the provisions of this Section 4.6, Purchaser shall
            not be required to assume the provisions of the Leasing Commission
            Agreement between Mortgagee and The Schultz Organization, LLC or the
            Leasing Commission Agreement between Mortgagee and
            Binswanger/Klatskin, it being agreed that such agreements shall be
            terminated on or before the


                                      -6-
<PAGE>

            Closing Date insofar as same pertain to the Properties, except that
            Purchaser shall pay a commission to The Schultz Organization in
            connection with the Lease between Mortgagee and Morristown Motors.
            Purchaser agrees to pay to the brokers identified on Exhibits M and
            M-1 annexed hereto, excluding The Schultz Organization, LLC,
            Binswanger/Klatskin, SBWE, Inc., Insignia, Cushman & Wakefield of
            New Jersey, Inc and Colliers Houston, any commissions that become
            due and payable upon the extension, renewal or expansion of any
            Lease to which such brokers would be entitled to a commission under
            their respective agreements. In addition, Purchaser agrees to pay to
            George Mintz & Company, Inc. the balance of the commission that will
            become payable if Boonton Electronics Corporation does not terminate
            its Lease pursuant to Paragraph 15 of the Second Amendment thereto
            and to pay to Newmark Real Estate of New Jersey, L.L.C. a commission
            in connection with the First Amendment to Lease dated February ,
            2003 between the landlord and Extreme Fitness, Inc. as tenant
            identified in clause (d) of Paragraph 9 hereof as the Expansion
            Space Lease. "

      15. Amendment of Representations and Warranties. Clause (f)(iii) of
Section 5.1 is hereby supplemented to provide that Sellers make no
representation or warranty that second installment of the leasing commissions
payable in connection with the original term of the Boonton Electronics
Corporation Lease, the commission relating to the initial term of the Morristown
Motors Lease or the commission relating to the First Amendment to the Extreme
Fitness Lease have been paid, it being agreed that Purchaser will pay such
commissions.

      16. Supplemental Environmental Provisions. (a) The parties acknowledge
that the DEP is requiring that Remediation Agreements be executed prior to the
closing with respect to the Properties known as 191 Talmadge Road, 16 Thornton
Road and 55 Webro Road and that the DEP will require that the sum of $100,000 be
paid to a trustee pursuant to Remediation Trust Fund Agreements as financial
security for performance under each such Remediation Agreement. The parties
further agree that, at the closing, the sum of $100,000 shall be paid from the
Allocable Purchase Price for each such Property directly to the trustee
designated under each Remediation Trust Fund Agreement. The applicable Sellers
agree to proceed expeditiously and in good faith to complete the remediation
required to be completed by


                                      -7-
<PAGE>

the Remediation Agreements and to obtain and forward to Purchaser promptly upon
receipt a copy of each "no further action letter" issued by the DEP. The
applicable Sellers shall hold and save Purchaser and its assigns harmless from
and against all loss, cost, damage, injury or expense arising out of the
performance of any remediation undertaken pursuant to the Remediation
Agreements, any breach by the applicable Seller under any Remediation Agreement
and any breach by the applicable Seller under this Paragraph 12. The provisions
of this Paragraph 12 shall survive the closing of title.

      (b) To the extent that the applicable Seller requires any documentation,
information, access or other cooperation from a tenant leasing space at 191
Talmadge Road, 16 Thornton Road or 55 Webro Road in order for the applicable
Seller to comply with a Remediation Agreement, and the tenant is required under
its Lease or at law to furnish same, upon request of the applicable Seller,
Purchaser agrees to proceed in good faith and with due diligence to obtain such
documentation, information access or other cooperation from a tenant. If any
such tenant fails or refuses to furnish such documentation, information, access
or other cooperation, Purchaser non-exclusively assigns to the applicable Seller
the right to institute litigation or other proceedings against the tenant to
obtain same, provided the applicable Seller shall not have the right to
terminate any lease, realize on any guaranty of such Lease or recourse to any
security posted under such Lease. Nothing contained herein shall be deemed a
waiver of Purchaser's right to enforce the Lease against such tenant.

      (c) Clause (k) of Section 9.4 of the Original Agreement is hereby modified
to provide that with respect to the Properties known as 191 Talmadge Road, 16
Thornton Road and 55 Webro Road, in lieu of providing a "letter of
non-applicability" from the DEP the applicable Sellers shall deliver to
Purchaser Remediation Agreements in form previously approved by Purchaser, and
that with respect to the Property known as 25 Eastmans Road, the applicable
Seller shall deliver a "deminimus quantity exemption" from the DEP.

      17. Title. The parties agree that Purchaser's title objections shall be
satisfied upon:

            (a) Sellers executing and delivering the closing documents required
to be delivered by Sellers, in form previously approved, including, without
limitation, the deeds,


                                      -8-
<PAGE>

affidavits of title, corporate resolutions and Certificate for each Property;

      (b) Sellers causing to be discharged of record all mortgages, assignments
of leases, lis pendens, judgments, tax sale certificates, financing statements
and other monetary liens against the Properties;

      (c) Sellers causing Raritan Building Associates Limited Partnership and
191 Talmadge Road Realty Holding, L.P. to be reinstated by the New Jersey
Treasurer; and

      (d) Sellers and Purchaser adjusting at closing all taxes, assessments and
other governmental charges pursuant to the Agreement of Sale.

      18. Conditions Precedent to Seller's Obligations. Section 9.1 of the
Original Agreement is hereby supplemented to include the following:

            "(d) the entry of a Consent Order in the Mortgage Foreclosure
            Proceeding approving a settlement agreement among Sellers and
            Mortgagee."

      19. Conditions Precedent to Purchaser's Obligations. Clause (e) of Section
9.2 of the Original Agreement is hereby deleted. Section 9.2 of the Original
Agreement is hereby supplemented to include the following:

            "(h) the entry of a Consent Order in the Mortgage Foreclosure
            Proceeding approving a settlement agreement among Sellers and
            Mortgagee and providing that on the Closing Date the Mortgagee."

      20. Closing Date. The first sentence of Section 9.3 of the Original
Agreement, as amended by Section 11 of the First Amendment, is hereby deleted
and the following is substituted therefor: "The closing of this transaction
shall be conducted on March 12, 2003 (the "Closing Date") at 10:00 A.M. If the
closing does not occur on such date, either party shall have the right to make
time of the essence upon three (3) business days notice to the other party."

      21. Closing Documents. (a) Clause (j) of Section 9.4 of the Original
Agreement is hereby amended to provide that the notices referred to therein must
be signed by each Seller, the Mortgagee and Purchaser.


                                      -9-
<PAGE>

      (b) Section 9.4 of the Original Agreement is hereby supplemented to
include the following provisions:

            "(r) written evidence that the Leasing Commission Agreement between
            Mortgagee and The Schultz Organization, LLC and the Leasing
            Commission Agreement between Mortgagee and Binswanger/Klatskin have
            been terminated insofar as same relate to the Properties;

            (s) written evidence that any commissions payable in connection with
            the existing terms of any Leases pursuant to which The Schultz
            Organization, LLC or Binswanger/Klatskin are entitled to any
            commissions have been paid in full, except the commission payable in
            connection with the Expansion Space Lease and the Morristown Motors
            Lease;

            (t) a termination of the management agreement between Mortgagee and
            The Schultz Organization to the extent same relates to any of the
            Properties;

            (u) an assignment in recordable form from Mortgagee of all rights
            under the Leases substantially in the form of ExhibitS BB annexed
            hereto;

            (v) assignments from Mortgagee in form reasonably acceptable to
            Purchaser of the roof warranties identified on Exhibit U annexed
            hereto;

            (w) evidence that all service contracts entered into by Mortgagee or
            The Schultz Organization with respect to the Properties have been
            terminated as of a date not later than thirty (30) days after the
            Closing Date without payment of any penalty or termination fee by
            Purchaser, provided that the foregoing requirement shall not apply
            to service contracts for snow removal, fire alarm/sprinkler
            monitoring ;

            (x) an assignment from Mortgagee of all rights under that certain
            Consent Order Regarding Assumption of Debtor's Real Property Lease
            and Granting Related Relief entered in the United States Bankruptcy
            Court, District of New Jersey, in Case No. 02-55654/MS and a notice
            from Mortgagee pursuant to Paragraph 13 of such Consent Order
            advising that the rights thereunder will no longer be exercised by
            Mortgagee;


                                      -10-
<PAGE>

            (y) an assignment from New York Distribution Center, L.P. of all its
            rights under that certain Consent Order Regarding Assumption of
            Debtor's Real Property Lease and Granting Related Relief entered in
            the United States Bankruptcy Court, District of New Jersey, on
            January 3, 2003 in Case No 02-55654/MS; and

            (z) written evidence that The Schultz Organization,
            Binswanger/Klatskin, SBWE, Inc., Insignia, Cushman & Wakefield of
            New Jersey, Inc and Colliers Houston have been paid in full for all
            commissions due in connection with the current terms of Leases for
            which they are entitled to a commission and that such entities waive
            the right to any future commissions in connection with renewals,
            extensions or expansions of such Leases."

      22. Additional Closing Documents. The Original Agreement is hereby
supplemented to include the following provision:

            "9.8 Provided Schultz Management Group executes and delivers to
            Purchaser an assignment of the following Service Contracts,
            Purchaser will execute an assumption thereof effective as of the
            Closing Date:

            1.    1120 Route 22, Bridgewater, New Jersey

                  i. Service Contract for Snow Removal Services between A & M
                  Landscaping and Schultz Management Group, Inc., as agent for
                  NJ Mortgage Acquisition, LLC, last executed October 31, 2002.

            2.    200 Middlesex Avenue, Carteret, New Jersey

                  i. Service Contract for Snow Removal Services between Kistler
                  Paving, Inc. and Schultz Management Group, Inc., as agent for
                  NJ Mortgage Acquisition, LLC, last executed November 6, 2002.

            3.    121 Fieldcrest Avenue, Edison, New Jersey

                  i. Service Contract for Snow Removal Services between Kistler
                  Paving, Inc. and Schultz Management Group, Inc., as agent for
                  NJ Mortgage Acquisition, LLC, last executed October 29, 2002.

            4.    1 Apollo Drive, Hanover, New Jersey


                                      -11-
<PAGE>

                  i. Service Contract for Snow Removal Services between USI
                  Landscape & Design, Inc. and Schultz Management Group, Inc.,
                  as agent for NJ Mortgage Acquisition, LLC, last executed
                  December 5, 2002.

                  ii. Central Station Installation and Service Contract between
                  AFA Protective Systems, Inc. and Schultz Management Group,
                  Inc., as agent for NJ Mortgage Acquisition, LLC, undated.

            5.    25 Eastmans Road, Hanover, New Jersey

                  i. Service Contract for Snow Removal Services between USI
                  Landscape & Design, Inc. and Schultz Management Group, Inc.,
                  as agent for NJ Mortgage Acquisition, LLC, last executed
                  December 5, 2002.

            6.    191 Talmadge Road, Edison, New Jersey

                  i. Service Contract for Snow Removal Services between Kistler
                  Paving, Inc. and Schultz Management Group, Inc., as agent for
                  NJ Mortgage Acquisition, LLC, last executed October 29, 2002.

                  ii. Central Station Installation and Service Contract between
                  AFA Protective Systems, Inc. and Schultz Management Group,
                  Inc., as agent for NJ Mortgage Acquisition, LLC, dated May 29,
                  2002."

      23. Closing Adjustments. Section 10.3 of the Original Agreement is hereby
supplemented by adding the words "Mortgagee or its property manager" after the
word "Seller" in the fourth line.

      (b) Article 10 of the Original Agreement is hereby supplemented to include
the following provisions:

            "10.5 Special Assessments. The parties acknowledge that the Property
            known as 585-587 Industrial Road, Carlstadt is encumbered by special
            assessments levied by The Borough of Carlstadt in aggregate amount
            of $32,193.03, plus interest from the date such assessments were
            payable. The applicable Seller is contesting the legality of such
            assessments. The parties agree that at the closing the amount of
            such assessments plus interest accrued thereon shall be


                                      -12-
<PAGE>

            deducted from the Allocable Purchase Price for such Property and
            paid to The Borough of Carlstadt in full payment of such
            assessments. The parties further agree that the letter forwarding
            such payement to The Borough of Carlstadt shall expressly provide
            that such payment is being made under protest and the applicable
            Seller reserves all rights to obtain a refund of such payment.
            Purchaser acknowledges that the applicable Seller will seek a refund
            of any such payment and agrees that any such refund shall be the
            property of the applicable Seller. Purchaser agrees to execute and
            deliver such documents as the applicable Seller may require to
            perfect its interest in any such refund. The provisions of this
            Section 10.5 shall survive the closing of title.

            10.6 CAM Reconciliation for 2002. The parties acknowledge that a
            reconciliation of CAM charges has not been completed for the
            calendar year 2002. The parties shall cooperate with The Schultz
            Organization to complete a reconciliation for CAM charges under the
            Leases for the calendar year 2002. Promptly after completing such
            reconciliation, Purchaser shall submit to the tenants under the
            Leases final billings for CAM charges for the calendar year 2002. To
            the extent that any tenants have overpaid CAM charges for the
            calendar year 2002, Purchaser shall be entitled to retain from the
            aggregate of all payments made by all tenants the amount of any such
            overcharges. The balance of any CAM charges collected from the
            tenants shall promptly be remitted to the applicable Seller. If any
            tenant does not pay such bill within one hundred twenty (120) days
            after billing, the applicable Seller shall have the right, at its
            sole cost and expense, to bring such actions or proceedings not
            affecting possession, the validity of the related Lease or any
            security held by Purchaser thereunder to collect any such amounts
            billed to a tenant, and Purchaser shall, at no cost to Purchaser,
            cooperate with such Seller in any such action.

            10.7 CAM Charges for 2003.

            (a) After the closing the Sellers will submit to Purchaser
            Statements ("Statements") indicating any CAM charges payable by
            tenants under the Leases in excess of the CAM charges actually paid
            by each tenant for any


                                      -13-
<PAGE>

            portion of Calendar Year 2003 prior to the Closing Date, together
            with reasonable back up information substantiating such charges.
            Purchaser shall promptly send to each tenant the applicable
            Statements. Upon receipt of any such sums shown on such Statement,
            Purchaser shall promptly remit such monies to the applicable
            Sellers. If any tenant does not pay such sum within one hundred
            twenty (120) days after billing, the applicable Seller shall have
            the right, at its sole cost and expense, to bring such actions or
            proceedings not affecting possession, the validity of the related
            Lease or any security held by Purchaser thereunder to collect any
            such amounts billed to a tenant, and Purchaser shall, at no cost to
            Purchaser, cooperate with such Sellers in any such action.

            (b) To the extent such monies are not collected, Purchaser shall, at
            Sellers' request, include the amount of such sums shown on the
            Statements in the CAM bills which Purchaser shall send to tenants
            for Calendar Year 2003; it being recognized that the final expense
            reimbursement payments due from tenants will not be finally
            calculated until at least the first quarter of 2004.

            (c) If Purchaser does not challenge the Statements prepared by
            Sellers within sixty (60) days of receipt by Purchaser of such
            Statements, the amounts contained in such Statements shall be
            conclusive for purpose of the 2003 CAM allocation between Sellers
            and Purchaser (hereinafter "Seller's Allocable Share"). If Purchaser
            does timely challenge any particular amount, such amount shall be
            subject to arbitration between the parties in accordance with the
            rules of the American Arbitration Association. Purchaser shall pay
            to Sellers Seller's Allocable Share out of the sums received from
            each tenant for CAM payments, provided that Purchaser is paid in
            full for all CAM charges incurred by Purchaser for the period
            between the Closing Date and December 31, 2003. In the event that
            the amount billed or to be billed by Purchaser to any tenant for
            2003 CAM is less than Seller's Allocable share, Purchaser shall pay
            to the applicable Seller Seller's Allocable Share at such time that
            it is determined that Seller's Allocable Share is less than the
            amount billed or to be billed to each tenant. If any tenant or
            Purchaser has not paid Sellers, Seller's


                                      -14-
<PAGE>

            Allocable Share in full by May 31, 2004, Purchaser agrees to assign
            to the applicable Sellers the right to Seller's Allocable Share and
            such Seller, at its sole cost and expense, may bring such action or
            proceedings not affecting possession, the validity of the related
            Lease or any security held by Purchaser thereunder to collect
            Seller's Allocable Share, and Purchaser shall, at no cost to
            Purchaser, cooperate with such Seller in any such action. Purchaser
            agrees that it will not compromise any sum due for CAM charges
            incurred by Sellers prior to the Closing Date, nor will Purchaser
            extend the date within which such CAM charges are payable."

      24. Additional Representations of Sellers. Clause (b) of Paragraph 9 of
the First Amendment is hereby deleted.

      25. Exhibits. Exhibits B-1, C-1, H-1, I-1, J-1, L-1, M-1, N-1, O-1, P-1,
Q-1, R-1, S-1 and T-1 are annexed hereto and relate to the Additional
Properties. Exhibits B, M and R annexed to the Agreement of Sale are hereby
replaced by Exhibits B, M and R annexed hereto. Exhibits F and K of the
Agreement of Sale are hereby deleted in their entirety and Exhibit K-1 annexed
hereto which identifies the security deposits currently being held with respect
to all of the Properties is substituted for Exhibits K and K-1. Exhibit B
annexed to the First Amendment is deleted in its entirety. Also annexed hereto
are supplements to Exhibits J, L and N annexed to the Agreement of Sale.

      26. Assignment. Pursuant to Section 12.2 of the Agreement of Sale,
Purchaser hereby designates Keystone NJP LLC as the entity to take title to the
Property identified as 16 Thornton Road, Oakland, hereby designates Keystone NJP
II to take title to the Properties identified as 110 Triangle Boulevard,
Carlsdadt, 121 Fieldcrest Avenue, Edison and 200 Middlesex Avenue, Carteret,
Keystone NJP III LLC to take title to the Properties identified as 25 Eastmans
Road, Hanover, 55 Webro Road, Clifton and 1 Apollo Drive, Hanover, Keystone NJP
IV LLC as the entity to take title to the Properties identified as 585/587
Industrial Road, Carlstadt and 1120 Route 22, Bridgewater and Keystone Talmadge
LLC as the entity to take title to the Property identified as 191 Talmadge Road,
Edison. Purchaser hereby assigns to such entities its rights hereunder insofar
as same pertain to the Properties to be acquired by such entities and Sellers
hereby consent to such assignments. Sellers further agrees that all closing
documents to be executed


                                      -15-
<PAGE>

by Purchaser with respect to the Properties being acquired by Keystone Talmadge
LLC, Keystone NJP LLC, Keystone NJP II LLC, Keystone NJP III LLC and Keystone
NJP IV LLC shall be executed by such entities and not by Purchaser and that, to
the extent Purchaser is obligated to assume any post closing obligations
hereunder, each entity taking title to one or more of the Properties shall only
be obligated to assume those obligations that relate to the Property or
Properties being acquired by it. Sellers and Purchaser agree that with respect
to the escrows to be established at the closing pursuant to the Original
Agreement as amended by this Second Amendment, such escrows shall be deemed to
be between only the applicable Seller and the entity actually taking title to
one or more of the Properties.

      27. Audit Rights. Purchaser and its consultants shall have the right for a
period of ninety (90) calendar days after the Closing Date to inspect the books
and records in the possession of Sellers with respect to the Properties and to
make copies thereof. Sellers agree to make such books and records available to
Purchaser and its consultants and to furnish any information in the possession
of Sellers relating to the operation of the Properties.

      28. Carlstadt Easement. Paragraph 15 of the First Amendment is hereby
deleted in entirety and the following provision is substituted therefor:

            "The parties acknowledge that Carlstadt Associates, Ltd. has been
            involved in litigation with E & K Success, Ltd. ("E&K") with respect
            to a storm water sewer easement on adjoining lands owned by E&K in
            matter entitled [           ], Civil Action Number [         ].
            Sellers represent and warrant to Purchaser that such litigation has
            been settled on the Court Record and that E & K has agreed pursuant
            to such settlement to grant to Carlstadt Associates, Ltd. an
            Easement Agreement for the installation of an underground storm
            water pipe. On the Closing Date, the applicable Seller shall execute
            and deliver to Purchaser an assignment of all rights against E&K,
            including all rights under the settlement agreement. The parties
            agree that there shall be deducted from the Allocable Price for the
            Property commonly known as 585-587 Industrial Road, Carlstadt, New
            Jersey, and deposited with the Escrow Agent the sum of $30,000 to be
            utilized by Purchaser to install the sewer line and perform such
            other work as may be necessary under the settlement. After the


                                      -16-
<PAGE>

            closing, Purchaser shall attempt to complete the installation of the
            sewer line and such other work and shall be entitled to
            reimbursement from such monies for the cost thereof as the work
            progresses. Any portion of the monies escrowed to complete such work
            remaining after Purchaser has been reimbursed for such cost of
            completion shall promptly be paid to the applicable Seller. If
            Purchaser has not exhausted the $30,000 escrow within five (5) years
            after the Closing Date, the balance of such escrow shall be paid to
            the applicable Seller."

      29. 585 Industrial Road, Carlstadt. Sellers have advised Purchaser that
Improved Packaging has filed litigation against the applicable Seller alleging
that such tenant sustained damages during the installation of the roof of the
Property known as 585 Industrial Road, Carlstadt. Purchaser agrees that, upon
reasonable notice to Purchaser, subject to the rights of any tenants, Seller and
its consultants shall have access to the building for purposes of inspection.
The provisions of the preceding sentence shall survive the closing of title.

      30. Miscellaneous. Except as amended hereby, all of the terms and
conditions of the Original Agreement are hereby ratified and confirmed and shall
remain in full force and effect. This Second Amendment shall be binding upon and
inure to the benefit of the successors and assigns of the parties hereto. This
Second Amendment shall be governed by, construed and enforced in accordance with
the laws of the State of New Jersey. This Second Amendment may not be amended or
modified, nor may any obligation hereunder be waived orally, and no such
amendment, modification or waiver shall be effective for any purpose unless it
is in writing and signed by the party against whom enforcement thereof is
sought. The captions and paragraph headings are provided for purposes of
convenience of reference only and are not intended to limit, define the scope
of, or aid in the interpretation of any of the provisions hereof. If there is
any inconsistency between the provisions of this Second Amendment and the
provisions of the Original Agreement, the provisions of this Second Amendment
shall govern. This Second Amendment may be executed and delivered in several
counterparts, each of which, when so executed and delivered, shall constitute an
original, fully enforceable counterpart for all purposes.

                           (Intentionally Left Blank)


                                      -17-
<PAGE>

      IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date set forth above.

                             Sellers:

                             INTERSTATE 78 OFFICE PARK, LTD.
                             A New Jersey Limited Partnership

                             By: Interstate 78 Office Park GP, L.L.C., A
                                 New Jersey Limited Liability Company,
                                 general partner

                                 By: United States Land Resources, L.P.,
                                     A New Jersey Limited Partnership,
                                     Manager

                                     By: United States Realty Resources,
                                         Inc., A New Jersey Corporation
                                         general partner


                                         By: /s/ Lawrence S. Berger
                                             -----------------------------------
                                             Name:  Lawrence S. Berger
                                             Title: President


                                         By: /s/ Lawrence S. Berger
                                             -----------------------------------
                                             Name:  Lawrence S. Berger
                                             Title: President


                                      -18-
<PAGE>

                            NEW YORK DISTRIBUTION CENTER, L.P.
                            A New Jersey Limited Partnership

                            By: Carteret-Industrial Road Management
                                Corp., A New Jersey Corporation,
                                general partner

                                By:    /s/ Lawrence S. Berger
                                       -----------------------------------------
                                Name:  Lawrence S. Berger
                                Title: President


                            RARITAN BUILDING ASSOCIATES LIMITED PARTNERSHIP,
                            A New Jersey Limited Partnership

                            By: Raritan Building GP, L.L.C.,
                                A New Jersey Limited Liability Company
                                general partner

                                By: United States Land Resources, L.P.,
                                    A New Jersey Limited Partnership, Manager

                                    By: United States Realty Resources, Inc.,
                                        A New Jersey Corporation general partner

                                           By: /s/ Lawrence S. Berger
                                              ----------------------------------
                                              Name:  Lawrence S. Berger
                                              Title: President


                             191 TALMADGE ROAD REALTY HOLDINGS, L.P.
                                    A New Jersey Limited Partnership

                                    By: 191 Talmadge GP, Inc.

                                    By: /s/ Lawrence S. Berger
                                       -----------------------------------------
                                       Name:  Lawrence S. Berger
                                       Title: President


                                      -19-
<PAGE>

                             CARLSTADT BUILDING REALTY HOLDINGS, L.P.
                             A New Jersey Limited Partnership

                             By: Carlstadt Triangle Property, Inc., A
                                 New Jersey Corporation, general partner

                                 By: /s/ Lawrence S. Berger
                                     -------------------------------------------
                                     Name:  Lawrence S. Berger
                                     Title: President


                             CARLSTADT ASSOCIATES, LTD.
                             A New Jersey Limited Partnership

                             By: Carlstadt Industrial Road GP, L.L.C.,
                                 A New Jersey Limited Liability Company,
                                 general partner

                                 By: United States Land Resources, L.P.,
                                     A New Jersey Limited Partnership, Manager

                                     By: United States Realty Resources,
                                         Inc., A New Jersey Corporation,
                                         general partner

                                         By: /s/ Lawrence S. Berger
                                             -----------------------------------
                                         Name:  Lawrence S. Berger
                                         Title: President


                             APOLLO ASSOCIATES, LTD.
                             A New Jersey Limited Partnership

                             By: One Apollo Drive Management Company, Inc.,
                                 general partner

                                         By: /s/ Lawrence S. Berger
                                             -----------------------------------
                                         Name:  Lawrence S. Berger
                                         Title: President


                                      -20-
<PAGE>

                             EASTMANS ROAD ASSOCIATES, LTD.
                             A New Jersey Limited Partnership

                             By: Eastmans Road GP, L.L.C., general partner

                                 By: United States Land Resources, L.P., manager

                                     By: United States Realty Resources, Inc.,
                                         general partner

                                         By: /s/ Lawrence S. Berger
                                             -----------------------------------
                                             Name: Lawrence S. Berger
                                             Title: President


                             WEBRO ASSOCIATES, LTD.
                             A New Jersey Limited Partnership

                             By: Webro Building GP, Inc., general partner

                                         By: /s/ Lawrence S. Berger
                                             -----------------------------------
                                             Name:  Lawrence S. Berger
                                             Title: President


                             OAKLAND BUILDING ASSOCIATES, LTD.
                             A New Jersey Limited Partnership

                             By: Oakland Building GP, Inc., general partner

                                         By: /s/ Lawrence S. Berger
                                             -----------------------------------
                                             Name:  Lawrence S. Berger
                                             Title: President


                             KEYSTONE NEW JERSEY ASSOCIATES, LLC

                             By: /s/ John P. DiCola
                                ------------------------------------------------
                                Name:  John P. DiCola
                                Title: Senior Vice President

                            JOINDER BY TITLE INSURER

      By execution hereof, the Title Insurer hereby consents to the execution
and delivery of this Agreement.

                                      CHICAGO TITLE INSURANCE
                                      COMPANY


                                      By: /s/ Ralph A. Romano
                                          --------------------------------------
                                          Name: Ralph A. Romano
                                          Title: R.V.P.


                                      -21-