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                                                                Exhibit 10 (ad)

                         AGREEMENT OF SALE AND PURCHASE

            THIS AGREEMENT is made as of the _____ day of August, 1997, by and
between GROUP THREE PROPERTIES, INC., a Pennsylvania corporation ("Seller") and
PENN SQUARE PROPERTIES, INC., a Pennsylvania corporation, or its assignee or
nominee ("Buyer").

                             W I T N E S S E T H :

             1. Agreement to Sell and Purchase. Seller agrees to sell to Buyer,
and Buyer agrees to purchase from Seller, subject to all of the terms and
conditions of this Agreement, the property situate in the Township of Bern,
Berks County, Commonwealth of Pennsylvania, consisting of the following:

                  (a) The Leasehold Estates in and to the Land; together with
all buildings and improvements ("Buildings") on the Land; together with all
appurtenances thereto; together with all rights, title and interest of Seller in
and to any lands lying in the bed of any street, opened or proposed, abutting
the Land; and together with all right, title and interest of Seller in and to
any unpaid award for the taking by eminent domain of any part of the Land and/or
Buildings. The "Land" shall mean those certain tracts of land more fully
described by metes and bounds on Exhibit A to this Agreement. The "Leasehold
Estates" shall mean the leasehold estates and rights granted, conveyed and
created pursuant to the Ground Leases. The "Ground Leases" shall mean: (i) that
certain Lease Agreement dated the 15th day of October, 1994, between The Reading
Regional Airport Authority, a municipal authority of the Commonwealth of
Pennsylvania (the "Authority") and Seller; and (ii) that certain Ground Lease
dated July 1, 1996 between the Authority and Seller. The Leasehold Estates, the
Buildings, and all of the other rights described above in this Section 1(a) are
herein collectively called the "Real Property". It is expressly understood and
agreed that the "Real Property" does not include fee simple title to the Land,
which fee simple title is owned by the Lessor under the Ground Leases.
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                                                                Exhibit 10 (ad)

                  (b) All fixtures, equipment, supplies, and other personal
property attached or appurtenant to, or located in or on, or used in connection
with the Real Property, which are not owned by the Tenant (as defined in
subparagraph 8(a) below; it being understood and agreed that the "Tenant" is a
collective reference to the subtenants under the Tenant Leases), and together
with all intangible personal property used in the ownership, operation or
maintenance of the Real Property, including without limitation, the items set
forth on Exhibit B to this Agreement (collectively, the "Personal Property").

                  (c) The Real Property and the Personal Property are sometimes
collectively referred to as the "Property".

            2. Purchase Price. The purchase price (the "Purchase Price") for the
Property, subject to adjustments as provided in this Agreement, shall be the sum
of Nine Million Six Hundred Thousand Dollars ($9,600,000), and shall be paid as
follows:

                  (a) Two Hundred Thousand Dollars ($200,000) shall be paid by
Buyer's check drawn to the order of First American Title Insurance Company
("Title Company") within two (2) business days after the expiration of the
Inspection Period. The term "Deposit" shall mean the aforesaid sum of Two
Hundred Thousand Dollars ($200,000) plus all interest which has accrued thereon.
The Deposit shall be held by the Title Company in an interest bearing account
pending consummation of this Agreement.

                  (b) The balance of the Purchase Price shall be paid at Closing
by wire transfer of immediate funds to an account of Seller (which account shall
be designated by written notice from Seller to Buyer no later than two (2)
business days prior to the Closing Date).

            3. Disposition of Deposit; Defaults.

                  (a) The Deposit shall be held in escrow and disbursed by Title
Company in accordance with the terms of this Agreement. If Closing is completed,
the Title Company shall pay the Deposit to Seller on account of the Purchase
Price.

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                  (b) (i) If Buyer, without the right to do so and in default of
its obligations under this Agreement fails to complete Closing, the Deposit
shall be paid to Seller as liquidated damages and not as a penalty. Buyer and
Seller acknowledge that the damages which may be incurred by Seller in the event
of Buyer's default are difficult to quantify as of the date of this Agreement;
the Deposit represents the parties' reasonable estimate of Seller's probable
future damages in the event of Buyer's default; and that the Deposit represents
fair and reasonable compensation to Seller in the event of Buyer's default. The
right of Seller to be paid the Deposit shall be Seller's exclusive and sole
remedy, and Seller waives any right to recover the balance of the Purchase
Price, or any part thereof, and the right to pursue any other remedy permitted
by law or in equity against Buyer.

                      (ii) If Seller, without the right to do so and in
default of its obligations under this Agreement fails to complete Closing, Buyer
shall have the right to be paid the Deposit, which right shall be in addition to
all other rights and remedies of Buyer under this Agreement, at law or in
equity, including without limitation the right to specific performance and
injunctive relief.

                  (c) In the event of a dispute between the parties with respect
to the Deposit, the Title Company may deposit the Deposit with the Court of
Common Pleas of Berks County, Pennsylvania, and commence an interpleader action.
Upon notifying Seller and Buyer of the commencement of such action, the Title
Company shall be released of all liability with respect to the Deposit, except
to the extent of accounting for any monies previously delivered by the Title
Company out of escrow. The Title Company shall not be liable to either Seller or
Buyer other than for the performance of its duties under this Agreement, its
negligence or intentional wrongdoing.

            4. Closing.

                  The closing of this transaction ("Closing") shall take place
at the offices of Wolf, Block, Schorr and Solis-Cohen, Twelfth Floor Packard
Building, 15th and Chestnut Streets, Philadelphia, Pennsylvania 19102. Closing
shall commence at 10:00 a.m. on October 31, 1997, or on such earlier date as
Buyer


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shall designate by at least five (5) days prior written notice to Seller (the
"Closing Date").

            5. Condition of Title.

                  (a) Title to the Property shall be good and marketable and
free and clear of all liens, restrictions, easements, encumbrances, leases,
tenancies and other title objections, except for the Ground Leases, the Tenant
Leases and the Permitted Encumbrances; and shall be insurable as such at
ordinary rates by the Title Company pursuant to an ALTA Leasehold Policy of
Title Insurance, 1970 Form B, amended October 17, 1970 and October 17, 1984. The
premium for the Leasehold Policy of Title Insurance will be paid by Buyer.
Anything to the contrary in this paragraph notwithstanding, Buyer will accept
title with the following exceptions set forth on Penn Title Insurance Company
Policies Nos. 79929-R and 81289-R: as to Policy 79929-R, exceptions 1, 2, 4, 5,
6, 7, 8, 10, 11, 12, 13, 14, 15 (limited to 1997 taxes), 16, 18 and 19; and as
to Policy 81289-R, exceptions 1, 2, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 15 and 16.

                  (b) If Seller is unable to convey title to the Property to
Buyer at Closing in accordance with the requirements of this Agreement, Buyer
shall have the options (i) of taking such title as Seller is able to convey with
abatement of the Purchase Price in the amount (fixed or ascertainable) of any
existing Monetary Liens or (ii) of terminating this Agreement. Notwithstanding
the foregoing, if title to the Property is not as described in Section 5(a) by
reason of any willful act by Seller, Buyer shall also be entitled to pursue all
other remedies available to Buyer at law or in equity.

                  (c) Buyer shall obtain from the Title Company a commitment for
Title Insurance ("Title Commitment") with respect to the Property prepared by
and at the cost of Buyer. Within five days after Buyer's receipt of the Title
Commitment and a new as-built survey of Property prepared by and at the cost of
Buyer, Buyer shall give to Seller notice ("Exception Notice") of any exceptions
to the title set forth in the Title Commitment which are not acceptable to Buyer
("Unacceptable Exceptions"). Buyer agrees that the Tenant Leases and the Ground
Leases shall not be Unacceptable Exceptions. Seller shall, within ten days from
the date of Seller's receipt of the Exception Notice, deliver to Buyer an
endorsement to the Title


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Commitment issued by the Title Company stating which, if any, Unacceptable
Exceptions the Title Company has removed from the Title Commitment; and if the
Title Company has not issued an endorsement to the Title Commitment removing all
of the Unacceptable Exceptions from the Title Commitment within ten days from
the date of Seller's receipt of the Exception Notice, then Buyer shall have the
right to terminate this Agreement. If Buyer does not terminate this Agreement
pursuant to the provisions of this subsection 5(c), then the exceptions
remaining on Schedule B, Section 2 of the Title Commitment which are not liens
securing repayment of monetary sums ("Monetary Liens") shall be the "Permitted
Encumbrances". Seller agrees fully to pay all Monetary Liens and cause all
Monetary Liens to be released and satisfied of record prior to the completion of
Closing.

            6. Possession.

                  Possession of the Property shall be given to Buyer at Closing,
subject only to the rights of the Tenant under Tenant Leases, by delivery of
Seller's general warranty Assignment of the Ground Leases duly executed and
acknowledged by Seller and in proper form for recording (the "Assignment"). The
Assignment shall expressly provide, inter alia, that Seller is released by the
Authority from liability under the Ground Leases and personal guaranties of
Frederick L. Snyder and Lyle Covert Beyer/Snyder.

            7. Apportionments; Transfer Taxes; Security Deposits.

                  (a) (i) Real estate taxes on the Real Property; water and
sewer rentals; Base Rent paid in advance under the Ground Leases and Additional
Rent payable in arrears under the Ground Leases; and base, minimum and/or fixed
rental, additional rental and other sums paid by the Tenant to the Seller prior
to Closing under the Tenant Leases shall be apportioned pro rata between Seller
and Buyer on a per diem basis as of the Closing Date; provided, however, that
there shall be no apportionment between Buyer and Seller at Closing with respect
to utility charges paid by the Tenant directly to utility companies pursuant to
the Tenant Leases.

                  (ii) If the Closing Date is not the first day of a calendar
month and if as of the Closing Date the Tenant has not paid the monthly
installment of base, minimum and/or fixed rental ("Delinquent Installment") due
under its Tenant


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Leases with respect to the month in which Closing occurs, then at Closing Buyer
shall receive a credit against the Purchase Price in an amount equal to the
portion of the Delinquent Installment applicable to the period of time from and
after the Closing Date and through the balance of the applicable month; and upon
Buyer's receipt of the Delinquent Installment from Tenant, Buyer shall pay the
full amount thereof to Seller.

                  (b) Each of Buyer and Seller shall pay one-half (1/2) of all
realty transfer taxes, if any, imposed by the Commonwealth of Pennsylvania and
all other governmental authorities upon the Deed and the conveyance of the Real
Property from Seller to Buyer.

                  (c) At Closing, Seller shall deliver to Buyer a certified
check in the amount of the Security Deposits paid under the Tenant Leases, and
all interest which has (or was required to) accrued thereon. The delivery of
such check shall not affect the amount of the Purchase Price.

            8. Representations and Warranties of Seller. Seller makes the
following representations and warranties to Buyer, which representations and
warranties are true and correct as of the date of this Agreement, and shall be
true and correct at and as of the Closing Date as though made both at and as of
the date of this Agreement and at and as of the Closing Date:

                  (a) The only leases and other agreements with respect to the
use and occupancy of the Property (herein collectively called the "Tenant
Leases"; and the tenants under each Tenant Leases being herein collectively
called the "Tenant") in effect are set forth on the Chart attached hereto as
Schedule 1.

                  (b) The Tenant Leases are valid and existing and in full force
and effect; the Tenant is in actual possession of the Property; and neither the
Tenant nor the Seller is in default of its respective obligations under the
Tenant Leases.


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<PAGE>

                  (c) The copies of the Tenant Leases previously delivered by
Seller to Buyer are true and complete copies of the Tenant Leases; the Tenant
Leases have not been amended, modified, or supplemented; and the Tenant does not
have any right to extend or renew the term of the Tenant Leases except as
expressly set forth in the Tenant Leases.

                  (d) The Tenant has not asserted any claim which could
adversely affect the right of the landlord to collect base, minimum or fixed
rental or additional rental from the Tenant; and no notice of default or breach
on the part of landlord under the Tenant Leases has been received by Seller from
the Tenant which has not been cured.

                  (e) Except as otherwise expressly listed on Schedule 2 hereto,
all construction, painting, repairs, alterations, improvements and other work
required to be performed by the landlord under the Tenant Leases, and all of the
other obligations of the landlord required to be performed under the Tenant
Leases as of the Closing Date, have been completed fully performed and paid for
in full by Seller.

                  (f) The term of the Tenant Leases commenced and will end on
the dates specified in the Chart attached hereto as Schedule 1.

                  (g) The rents and other payments set forth in the Tenant
Leases are the actual rents, income and charges presently being collected by
Seller under the Tenant Leases; and all minimum rent payable under the Tenant
Leases is payable monthly in advance.

                  (h) Except as set forth in the Tenant Leases, the Tenant is
not entitled to any concession, allowance, rebate or refund; and the allowances,
if any, specified in the Tenant Leases have been fully recovered by the Tenant
thereunder.

                  (i) The Tenant has not prepaid any base rental, minimum
rental, fixed rental or additional rental or other charges for more than the
current month under the Tenant Leases.

                  (j) Neither the Tenant Leases nor the rental or other amounts
payable under the Tenant Leases has been assigned,


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pledged or encumbered, except to Seller's lenders, which assignments will be
terminated at Closing.

                  (k) No security deposit has been paid by the Tenant under the
Tenant Leases, except as set forth on the Chart attached hereto as Schedule 1.

                  (l) No brokerage or leasing commissions or other compensation
is or will be due and payable to any party with respect to or on account of the
Tenant Leases or any extensions or renewals thereof or any other actions by the
Tenant thereunder.

                  (m) Except as expressly set forth in the Tenant Leases, the
Tenant does not have any right or option to acquire to the Property or any
portion thereof.

                  (n) Seller has not received any written notice ("Defect
Notice") from any insurance company which has issued a policy with respect to
the Property or from any board of fire underwriters (or other body exercising
similar functions) claiming any defects or deficiencies in the Property or
suggesting or requesting the performance of any repairs, alterations or other
work to the Property.

                  (o) As of the Closing Date there shall be no management,
service, equipment, supply, security, maintenance, construction, concession or
other agreements with respect to or affecting the Property, except for any
agreements under which only the Tenant is bound.

                  (p) No employee of Seller who performs services at or in
connection with the Property is covered by an employment agreement or union
contract; no demand has been made upon Seller for recognition of a union or
collective bargaining agent for the employees of Seller at the Property; and
none of the employment arrangements with respect to Seller's employees will be
binding upon Buyer or any subsequent owner of the Property after Closing.

                  (q) Except as otherwise set forth on Schedule 3, there are no
outstanding uncured written notices received by Seller of any violation
("Violation") of any applicable law, ordinance, code, rule, order, regulation or
requirement of any governmental authority with respect to the Property.


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                  (r) Exhibit D sets forth the only fire and extended coverage
insurance policies ("Policy") maintained by Seller with respect to the Property;
the Policy is in full force and effect and all premiums due thereunder has been
paid; and neither Seller nor (to Seller's knowledge) any Tenant has received any
notice from the insurance companies which issued the Policy, indicating that the
Policy will not be renewed or will be renewed at a higher premium than is
presently payable therefor.

                  (s) There is no action, suit or proceeding pending or, to the
knowledge of Seller, threatened against or affecting Seller or the Property or
any portion thereof or the Tenant Leases or relating to or arising out of the
ownership, management or operation of the Property, in any court or before or by
any federal, state, county or municipal department, commission, board, bureau or
agency or other governmental instrumentality.

                  (t) Seller has not received any notice of any condemnation
proceeding or other proceedings in the nature of eminent domain ("Taking") in
connection with the Property, and to Seller's knowledge no Taking has been
threatened.

                  (u) All of the books, records, information, data and other
items supplied by Seller to Buyer with respect to Seller or the Property are
true, complete and correct in all material respects.

                  (v) To the best of Seller's knowledge: there is no presently
existing violation at the Property of any environmental law or regulation; no
contamination is present at the Property; and no underground storage tanks,
asbestos or PCBs are present at the Property.


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                  (w) The copies of the Ground Leases attached hereto as Exhibit
C are true and complete copies thereof, and the same have not been amended,
modified or supplemented; the Landlord under the Ground Leases is the Authority;
the Ground Leases are in full force and effect; no default or breach exists
under the Ground Leases on the part of the Authority and/or on the part of the
Seller, and no event or omission has occurred which with the giving of notice or
lapse of time, or both, would constitute a default or breach under the Ground
Leases on the part of the Authority or on the part of the Seller; there are no
other agreements between the Seller and the Authority nor between the Seller and
any prior owners of the Real Property which have not been fully rescinded and
rendered null and void; the Base Rent payable under each of the Ground Leases is
at the following rates: years 1-5 - $________; years 6-10 - $_______; years
11-15 - $_______; years 16-20 - $_______; and the Base Rent abatement specified
in Section 3.1(b) of the Ground Lease dated July 1, 1996 remains in effect and
has not ended and the contingencies described in clauses (ii) and (iii) of
Section 3.1(b) of the Ground Lease dated July 1, 1996 have not occurred.

            9. Time. In computing the number of days for purposes of this
Agreement, all days shall be counted, including Saturdays, Sundays and holidays;
provided, however, that if the final day of any time period provided in this
Agreement shall end on a Saturday, Sunday or legal holiday, then the final day
shall extend to 5:00 p.m. of the next full business day. For the purposes of
this Section 9, the term "holiday" shall mean a day other than a Saturday or
Sunday on which banks in the state in which the Real Property is located are or
may elect to be closed.

            10. Operations Prior to Closing. Between the date of the execution
of this Agreement and Closing:

                  (a) Seller shall, at its expense: perform all of its
obligations under the Tenant Leases and the Ground Leases; and cure all notices
of any Violations and/or Defect Notices issued prior to Closing.

                  (b) Seller shall not enter into any agreement to modify, amend
or otherwise alter any of the terms or provisions of the Tenant Leases or the
Ground Leases; and Seller shall not enter into a new lease or other agreement
with respect to the use


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or occupancy of the Property, without prior written approval of Buyer.

                  (c) Omitted intentionally.

                  (d) (i) Buyer, its attorneys, accountants, architects,
engineers and other representatives shall be afforded access to the Property and
to all books, records and files relating thereto from time to time prior to
Closing for the purposes of inspections, preparation of plans, taking of
measurements, making of surveys, making of appraisals, and generally for the
ascertainment of the condition of the Property, including but not limited to the
physical and financial condition of the Property; and there shall be furnished
to Buyer all plans and specifications, engineering reports, feasibility studies,
operating statements, governmental permits and approvals, contracts, leases,
surveys, title information and other documentation concerning the Property in
the possession of Seller and/or Seller's management agent for the Property.

                    (ii) Buyer agrees to indemnify, defend and reimburse Seller
for all costs, expenses (including, without limitation, attorney's fees,
consultant and expert fees and court costs) loss and liabilities suffered or
incurred by Seller as the result of any bodily injuries to persons or properties
caused by Buyer's entry upon the Property prior to Closing pursuant to the
provisions of this Section 10(d).

                  (e) Promptly after receipt thereof by Seller, Seller shall
deliver to Buyer the following:

                        (i) a copy of any notice of default given or received
under the Tenant Leases;

                        (ii) a copy of any tax bill, notice or statement of
value, or notice of change in a tax rate affecting or relating to the Property;

                        (iii) a copy of any notice of an actual or alleged
Violation;

                        (iv) a copy of any notice of Taking; and


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                        (v) a copy of any notice given or received under the
Ground Leases.

                  (f) Seller shall deliver for execution by the Tenant a written
certification which shall be prepared by Buyer's counsel (utilizing the form
attached to this Agreement as Exhibit E, but modified and supplemented by
Buyer's counsel to reflect the terms and provisions of the Tenant Leases) (each
such certification being herein called a "Tenant Estoppel Certificate"); and
Seller shall obtain an executed Tenant Estoppel Certificate (dated no more than
twenty (20) days prior to the Closing Date) from the Tenant. Seller shall
deliver to Buyer a copy of the executed Tenant Estoppel Certificate obtained by
Seller, promptly after Seller's receipt thereof.

                  (g) Seller shall deliver for execution by the Tenant a
Subordination, Non-Disturbance and Attornment Agreement (SNDA) in the form
reasonably required by Buyer's lenders, if any; and Seller shall obtain an
executed SNDA from the Tenant. Seller shall deliver to Buyer a copy of the
executed SNDA delivered to Seller promptly after receiving such SNDA.

                  (h) Seller shall deliver for execution by the Authority a
written certification which shall be prepared by Buyer's counsel (utilizing the
form attached to this Agreement as Exhibit F, but modified and supplemented by
Buyer's counsel to reflect the terms and provisions of the Ground Leases and the
representations and warranties of Seller set forth in Section 8) ("Authority
Estoppel Certificate"); and shall obtain an executed Authority Estoppel
Certificate (dated no more than twenty (20) days prior to the Closing Date) from
the Authority. Seller shall deliver to Buyer a copy of the executed Authority
Estoppel Certificate delivered to Seller promptly after receiving such Authority
Estoppel Certificate. Seller shall pay all costs, fees, charges and expenses
imposed by the Authority for the issuance of the Authority Estoppel Certificate
and for the granting of the consent by the Authority of the assignment of the
Ground Leases to Buyer.

            11. Survival. The representations and warranties of Seller set forth
in Section 8(e)(j)(l)(n)(o)(p)(q)(s)(t)(u) and (v) shall survive Closing for a
period of 12 months from Closing and thereafter if a notice of breach is given
to Seller with such 12-monthly period. The obligations of Seller and Buyer
pursuant


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to Sections 16,17 and 20 of this Agreement shall survive Closing without limit.
Except as otherwise provided in the preceding two sentences, the agreements of
Seller and Buyer set forth in this Agreement shall not survive Closing and shall
merge into the delivery of the Assignment at Closing.

            12. Casualty.

                  (a) Seller shall maintain the Policy in effect until Closing,
and shall deliver to Buyer, within ten (10) days after the date of this
Agreement, an endorsement to the Policy evidencing that the Policy is in effect,
that the Policy will not be canceled or materially modified without at least
thirty (30) days prior written notice to Buyer, and that Buyer has been added to
the Policy as an additional insured party, as its interests may appear. If
Closing is not completed under this Agreement, Buyer agrees to deliver to
Seller, upon request, a written direction to the insurance company directing
that Buyer's name as an additional insured party be deleted therefrom. If
Closing is completed under this Agreement, Seller shall be entitled to all
rebates and refunds of any prepaid premiums under the Policy.

                  (b) If at any time prior to the completion of Closing any
portion of the Property is destroyed or damaged as a result of fire or any other
casualty ("Casualty"), Seller shall promptly give written notice ("Casualty
Notice") thereof to Buyer. If the Property is the subject of a Casualty, Buyer
shall have the right, at its sole option, of terminating this Agreement unless,
(i) the cost fully to repair or restore such damage is less than Twenty-Five
Thousand Dollars ($25,000) and sufficient insurance proceeds are available fully
to restore such damage, and (ii) the insurance company issuing the Policy has
confirmed in writing prior to the end of such thirty (30) day period that such
Casualty is covered by the Policy and that no defense to payment of the claim
exists, and (iii) such Casualty will not result in the Tenant or the Authority
terminating the Tenant Leases or the Ground Leases or asserting a right to
terminate the Tenant Leases or the Ground Leases, and (iv) any loan commitment
obtained by Buyer for financing to acquire the Property is not canceled or
suspended as a result of such Casualty. In the event that insurance proceeds are
not available, Seller shall have the right, but not the obligation, at its own
expense, to provide the funds to restore and shall receive from Buyer, upon
recovery from the carrier, the funds so expended. If Buyer does not terminate


                                      13
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this Agreement, the proceeds of any insurance with respect to the Property paid
between the date of this Agreement and the Closing Date shall be paid to Buyer
at the time of Closing and all unpaid claims and rights in connection with
losses to the Property shall be assigned to Buyer at Closing without in any
manner affecting the Purchase Price.

                  (c) If the Property is the subject of a Casualty, but Buyer
does not have the right to terminate this Agreement pursuant to the provisions
of Section 12(b) (or Buyer does not exercise such right), then Seller shall
promptly cause all temporary repairs to be made to the Property as shall be
required to prevent further deterioration and damage to the Property; provided,
however, that any such repairs shall first be approved by Buyer. Seller shall
have the right to be reimbursed from the proceeds of any insurance with respect
to the Property whenever said insurance proceeds are received by the Buyer for
the cost of all such repairs made pursuant to this Section 12(c). Except for the
obligation of Seller to repair the Property set forth in this Section 12(c),
Seller shall have no other obligation to repair any Casualty damage in the event
Buyer does not elect to terminate this Agreement pursuant to the provisions of
Section 12(b), and in such event, Buyer shall accept the Property at Closing as
damaged or destroyed by the Casualty.

            13. Eminent Domain. If at any time prior to the completion of
Closing: a Taking affects all or any part of the Property, or if any proceeding
for a Taking is commenced, or if notice of the contemplated commencement of a
Taking is given, Seller shall promptly give written notice thereof to Buyer, and
Buyer shall have the right, at its sole option, of terminating this Agreement by
written notice to Seller. If Buyer does not terminate this Agreement, the
Purchase Price shall be reduced by the total of any awards or damages received
by Seller and Seller shall, at Closing, assign to Buyer all of Seller's right,
title and interest in and to any awards or damages to which Seller may have
become entitled or may thereafter be entitled by reason of any exercise of the
power of eminent domain or condemnation with respect to or for the Taking of the
Property or any portion thereof.

            14. Conditions of Buyer's Obligations.


                                      14
<PAGE>

                  (a) The obligations of Buyer under this Agreement are subject
to the satisfaction at the time of Closing of each of the following conditions
(any one of which may be waived in whole or in part in writing by Buyer at or
prior to Closing):

                        (i) all of the representations and warranties by Seller
set forth in this Agreement shall be true and correct in all material respects;

                        (ii) no representation or warranty by Seller contained
in this Agreement shall contain any materially untrue statement or shall omit a
material fact necessary to make the statement of fact therein recited not
misleading;

                        (iii) Seller shall have performed all covenants,
agreements and conditions required by this Agreement to be performed by Seller
prior to or as of the Closing Date; and

                        (iv) Buyer shall have received the executed Tenant
Estoppel Certificate, SNDA and Authority Estoppel Certificate.

                  (b) Failure of Condition. In the event any of the conditions
set forth in Section 14(a) are not satisfied as of the Closing Date, Buyer shall
have the right (in addition to all other rights and remedies available to Buyer
under this Agreement, at law or equity), at Buyer's sole option, to (i)
terminate this Agreement or (ii) complete Closing notwithstanding the
unsatisfied condition.

                  (c) Inspection Contingency.

                        (i) Buyer shall, during the period ("Inspection Period")
from the date of this Agreement to the date occurring forty-five (45) days after
the date of this Agreement, have the opportunity to examine the Property, the
Ground Leases, the Tenant Leases, the Policy, the Permitted Encumbrances, any
items to be delivered by Seller to Buyer, and to conduct such other inspections
of the Property as Buyer, in its discretion, may elect.

                        (ii) Seller acknowledges that Buyer may commission,
prior to Closing, at Buyer's sole cost and expense, an investigation (without
limitation) of: compliance with


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environmental laws, the presence of contaminants on, over, under, migrating from
or affecting the Property.

                        (iii) Seller will cooperate with Buyer and Buyer's
agents in Buyer's investigation, including without limitation: (A) complying
with requests for information and records; (B) warranting that responses to such
requests are true and complete; (C) assisting Buyer in obtaining governmental
agency or other records and upon Buyer's request communicating directly with any
governmental agencies; and (D) granting Buyer access to the Property including,
without limitation, access for collecting surface or subsurface samples of soil,
vegetation or water, or samples from buildings and other improvements located on
the Property, including samples from walls, floors, ceilings, plenums, paved
areas and other areas the taking of which samples may necessitate some damage to
the buildings, which damage shall be repaired by Buyer, at Buyer's sole cost and
expense, other improvements, and installing groundwater monitoring wells.

                        (iv) Buyer shall have the right, at Buyer's sole option,
to terminate this Agreement (for any reason whatsoever) on or prior to the
second business day to occur after the date on which the Inspection Period ends.

            15. Items to be Delivered at Closing.

                  (a) By Seller. At Closing, Seller shall deliver to Buyer
the following:

                        (i) Assignment. The Assignment of the Ground Leases,
duly executed and acknowledged by Seller and in proper form for recording,
together with original executed copies of the Ground Leases.

                        (ii) Bill of Sale. A Bill of Sale for the Personal
Property, duly executed and acknowledged by Seller and in proper form for
recording .

                        (iii) Assignments of Leases. An assignment in the form
of Exhibit G of the Tenant Leases, duly executed and acknowledged by Seller and
in proper form for recording, together with an original executed copy of the
Tenant Leases and a letter, duly executed by Seller, in form satisfactory to
Buyer addressed to the tenant.


                                      16
<PAGE>

                        (iv) Certificates, Etc. An assignment, duly executed and
acknowledged by Seller, of (and delivery to Buyer of originals or copies of)
(all of the following now in the possession of Seller): all certificates of
occupancy and all other licenses, permits, authorizations, consents,
certificates and approvals for the Property; all fees, escrow and/or security
funds; all certificates issued by the local Board of Fire Underwriters (or other
body exercising similar functions); all plans, specifications and project
manuals for the Property; all guarantees, bonds and warranties with respect to
the Property (together with original counterparts of such instruments); and all
keys to the Property.

                        (v) Tenant Estoppel Certificates. An original executed
counterpart of the Tenant Estoppel Certificate and the SNDA.

                        (vi) Authority Estoppel Certificate. An original
executed counterpart of the Authority Estoppel Certificate.

                        (vii) Resolutions; Title Company Affidavits. Such
resolutions and certificates as the Title Company shall require to evidence the
due authorization of the execution and performance of this Agreement and the
documents to be delivered pursuant hereto; and all affidavits, indemnities and
other agreements required by the Title Company to permit it to issue to Buyer
the Leasehold Policy of Title Insurance required pursuant to Section 5(a).

                        (viii) Statements. A statement, certified by Seller (and
accompanied with all relevant back-up documentation) setting forth all
information reasonably necessary or reasonably required to permit Buyer to
calculate and collect after Closing all payments of additional rent and other
charges due under the Tenant Leases and to permit Buyer to calculate and pay
after Closing all payments due under the Ground Leases.

                        (ix) Conveyance of Awards. All proper instruments for
the conveyance of the awards referred to in Sections 1(a) and 13.


                                      17
<PAGE>

                        (x) Other Documents. Any other documents required to be
delivered by Seller pursuant to any other provisions of this Agreement.

                   (b) By Buyer. At Closing, Buyer shall deliver to Seller the
following:

                        (i) Purchase Price. The portion of the Purchase Price
payable pursuant to Section 2(b).


                        (ii) Assumption Agreements. An assumption agreement, in
the form of Exhibit G of the Tenant Leases, duly executed and acknowledged by
Buyer and in proper form for recording.

                        (iii) Other Documents. Any other document required to be
delivered by Buyer pursuant to any other provisions of this Agreement.

            16. Reports. For the period of time commencing on the date of this
Agreement and continuing through the first anniversary of the Closing Date, and
without limitation of the other document production otherwise required of Seller
under this Agreement, Seller shall, from time to time, upon reasonable advance
written notice from Buyer, provide to Buyer and its representatives: (i) access
to all financial and other information pertaining to the period of Seller's
ownership and operation of the Property, which information is relevant and
reasonably necessary, in the opinion of Buyer's outside, third party accountants
("Accountants") to enable Buyer and its Accountants to prepare financial
statements in compliance with any and all of (a) Rule 3-05 or Rule 3-14 of
Regulation S-X of the Securities and Exchange Commission (the "Commission"), as
applicable to Buyer; (b) any other rule issued by the Commission and applicable
to Buyer; and (c) any registration statement, report or disclosure statement
filed with the Commission by, or on behalf of Buyer; and (ii) a representation
letter, in form specified by, or otherwise satisfactory to the Accountants,
signed by the individual(s) responsible for Seller's financial reporting, as
prescribed by generally accepted auditing standards promulgated by the Auditing
Standards Division of the American Institute of Certified Public Accountants,
which representation


                                      18
<PAGE>

letter may be required by the Accountants in order to render an opinion
concerning Seller's financial statements.

            17. Brokerage.

                  (a) Buyer represents and warrants to Seller that Buyer has
dealt with no broker, finder or other intermediary in connection with this sale;
and Buyer agrees to indemnify, defend and save and hold harmless Seller of and
from any and all cost, loss or expense incurred by Seller as the result of a
breach by Buyer of its representations and warranties set forth in this Section
17.

                  (b) Seller represents and warrants to Buyer that Seller has
dealt with no broker, finder or other intermediary in connection with this sale;
and Seller agrees to indemnify, defend and save and hold harmless Buyer of and
from any and all costs, loss or expense incurred by Buyer as the result of a
breach by Seller of its representations and warranties set forth in this Section
17.

            18. No Other Representations. Buyer acknowledges that neither Seller
nor anyone acting, or purporting to act, on behalf of Seller, has, except as
expressly set forth in this Agreement, made any representation or warranty with
respect to the Property.

            19. Assignability. Buyer shall have the right to assign this
Agreement and its rights hereunder; and any assignee of Buyer shall be entitled
to exercise all of the rights and powers of Buyer hereunder at Closing.

            20. FIRPTA.

                  (a) Section 1445 of the Internal Revenue Code of 1986, as
amended (the "Code") provides that a transferee of a United States real property
interest must withhold tax if the transferor is a foreign person. To inform
Buyer that withholding of tax is not required upon the disposition by Seller of
a United States real property interest, the undersigned parties executing this
Agreement on behalf of Seller hereby certify the following on behalf of Seller:


                                      19
<PAGE>

                        (i) Seller is not a foreign corporation, foreign
partnership, foreign trust, or foreign estate (as those terms are defined in the
Code and Income Tax Regulations);

                        (ii) Seller's U.S. employer identification number is
_______________; and

                        (iii) Seller's office address is: 4641 Pottsville Pike,
Suite E, Reading, PA 19605.

Seller, and the parties executing this Agreement on behalf of Seller, understand
that this certification may be disclosed to the Internal Revenue Service by
Buyer and that any false statement made here could be punished by fine,
imprisonment, or both. Under penalties of perjury, the undersigned parties
executing this Agreement on behalf of Seller declare that they have examined
this certification and to the best of their knowledge and belief, it is true,
correct and complete; and they further declare that they have authority to sign
this document on behalf of Seller.

                  (b) Seller, and the parties executing this Agreement on behalf
of Seller, shall deliver to Buyer at Closing, a restatement of the above
certifications of Seller and of the parties executing this Agreement on behalf
of Seller in the form attached to this Agreement as Exhibit H.

            21. Notices.

                  (a) All notices, demands, requests or other communications
from each party to the other required or permitted under the term of this
Agreement shall be in writing and, unless and until otherwise specified in a
written notice by the party to whom notice is intended to be given, shall be
sent to the parties at the following respective addresses:

                  if intended for Seller:

                  Group Three Properties, Inc.
                  Cross Roads Corporate Center
                  4641 Pottsville Pike, Suite E
                  Reading, PA  19605
                  Fax No.:  610-926-4924


                                      20
<PAGE>

                  if intended for Buyer:

                  The Widener Building, Suite 200
                  One South Penn Square
                  Philadelphia, PA 19107
                  Attention:  Jeffrey E. Kelter
                  Fax No.:  (215) 972-0819

Notices may be given on behalf of any party by its legal counsel.

                  (b) Each such notice, demand, request or other communication
shall be given (i) against a written receipt of delivery, or (ii) by registered
or certified mail of the United States Postal Service, return receipt requested,
postage prepaid, or (iii) by a nationally recognized overnight courier service
for next business day delivery, or (iv) via telecopier or facsimile transmission
to the facsimile number listed above, provided, however, that if such
communication is given via telecopier or facsimile transmission, an original
counterpart of such communication shall concurrently be sent in either the
manner specified in clause (i) or (iii) above.

                  (c) Each such notice, demand, request or other communication
shall be deemed to have been given upon the earliest of (i) actual receipt or
refusal by the addressee, or (ii) deposit thereof at any main or branch United
States post office if sent in accordance with section (b)(ii) above or (iii)
deposit thereof with the courier if sent pursuant to section (b)(iii) above.

            22. Miscellaneous.

                  (a) Captions. The captions in this Agreement are inserted for
convenience of reference only; they form no part of this Agreement and shall not
affect its interpretation.

                  (b) Successors and Assigns. This Agreement shall be binding
upon and shall inure to the benefit of the parties and their respective
successors and assigns.

                  (c) Entire Agreement; Governing Law. This Agreement contains
the entire understanding of the parties with respect to the subject matter
hereof, supersedes all prior or other negotiations, representations,
understandings and


                                      21
<PAGE>

agreements of, by or among the parties, express or implied, oral or written,
which are fully merged herein. The express terms of this Agreement control and
supersede any course of performance and/or customary practice inconsistent with
any such terms. Any agreement hereafter made shall be ineffective to change,
modify, discharge or effect an abandonment of this Agreement unless such
agreement is in writing and signed by the party against whom enforcement of such
change, modification, discharge or abandonment is sought. This Agreement shall
be governed by and construed under the laws of the Commonwealth of Pennsylvania.

                  (d) Provisions Separable. The provisions of this Agreement are
independent of and separable from each other, and no provision shall be affected
or rendered invalid or unenforceable by virtue of the fact that for any reason
any other provision may be invalid or unenforceable in whole or in part.

                  (e) Waiver of Tender of Assignment and Purchase Monies. The
tender of an executed Assignment by Seller and the tender by Buyer of the
portion of the Purchase Price payable at Closing are mutually waived, but
nothing in this Agreement shall be construed as a waiver of Seller's obligation
to deliver the Assignment and/or of the concurrent obligation of Buyer to pay
the portion of the Purchase Price payable at Closing.

                  (f) Gender, etc. Words used in this Agreement, regardless of
the number and gender specifically used, shall be deemed and construed to
include any other number, singular or plural, and any other gender, masculine,
feminine or neuter, as the context indicates is appropriate.

                  (g) Counterparts. This Agreement may be executed in any number
of counterparts, each of which shall be deemed to be an original as against any
party whose signature appears thereon, and all of which shall together
constitute one and the same instrument. This Agreement shall be binding when one
or more counterparts hereof, individually or taken together, shall bear the
signatures of all of the parties reflected on this Agreement as the signatories.

                  (h) Exhibits. All exhibits attached to this Agreement are
incorporated by reference into and made a part of this Agreement.


                                      22
<PAGE>

                  (i) No Waiver. Neither the failure nor any delay on the part
of either party to this Agreement to exercise any right, remedy, power or
privilege under this Agreement shall operate as a waiver thereof, nor shall any
single or partial exercise of any right, remedy, power or privilege preclude any
other or further exercise of the same or of any other right, remedy, power or
privilege, nor shall any waiver of any right, remedy, power or privilege with
respect to any occurrence be construed as a waiver of any such right, remedy,
power or privilege with respect to any other occurrence. No waiver shall be
effective unless it is in writing and is signed by the party asserted to have
granted such waiver.

                  (j) Interpretation. No provision of this Agreement is to be
interpreted for or against either party because that party or that party's legal
representative or counsel drafted such provision.

                  (k) Attorney's Fees. In connection with any litigation arising
out of this Agreement, the prevailing party shall be entitled to recover all
costs incurred, including reasonable attorney's fees.

                  (l) Buyer's Exercise of Right to Terminate. If Buyer desires
to terminate this Agreement pursuant to any of the provisions of this Agreement,
Buyer shall do so by giving written notice of termination to Seller. Upon any
such termination, the Deposit shall be paid to Buyer (and each of Seller and
Buyer shall deliver written instructions to the Title Company to pay the Deposit
to Buyer); and except as otherwise expressly provided in this Agreement, this
Agreement shall be and become null and void and neither party shall have any
further rights or obligations under this Agreement.


                                      23
<PAGE>

            IN WITNESS WHEREOF, intending to be legally bound, the parties have
executed this Agreement as a sealed instrument as of the day and year first
above written.

Witness:                                  SELLER

                                          GROUP THREE PROPERTIES, INC.


                                          By: /s/ Frederick Snyder
                                              -------------------------------
                                              President  August 13, 1997



                                          BUYER

                                          PENN SQUARE PROPERTIES, INC.


                                          By: /s/ Jeffrey E. Kelter
                                              -------------------------------
                                              President  August 13, 1997


                                      24
<PAGE>

                                   SCHEDULE 1

                                  Tenant Leases
<TABLE>
<CAPTION>
-------------------------------------------------------------------------------
                                                                    Ending Date
                   Date of                          Commencement        of
Date of Lease    Amendments       Name of Tenant    Date of Term       Term
-------------------------------------------------------------------------------
<S>              <C>            <C>                 <C>             <C>
                                Premium Beverage
                                Packers, Inc.
-------------------------------------------------------------------------------
                                Galeo & Hults, Inc.
-------------------------------------------------------------------------------
                                R. L. Johnson Company
-------------------------------------------------------------------------------
                                The Glidden Company
-------------------------------------------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------

-------------------------------------------------------------------------------
</TABLE>

         (To be completed by Seller within 5 days after the date of this
                               agreement of Sale)
<PAGE>

                                   SCHEDULE 2

                       LIST OF CONSTRUCTION ITEMS REQUIRED
                    TO BE PERFORMED BY LANDLORD AFTER CLOSING
                            PURSUANT TO SECTION 8(e)

         (To be completed by Seller within 5 days after the date of this
                               agreement of Sale)


<PAGE>

                                   SCHEDULE 3

                       LIST OF EXISTING VIOLATION NOTICES
                            PURSUANT TO SECTION 8(q)

         (To be completed by Seller within 5 days after the date of this
                               agreement of Sale)


<PAGE>

                                    EXHIBIT A

                          LEGAL DESCRIPTION OF THE LAND
<PAGE>

                                    EXHIBIT B
                            LIST OF PERSONAL PROPERTY

            (1) All architectural, mechanical, engineering and other plans and
specifications relating to the Property.

            (2) All percolation, and other soil, topographical, and traffic
studies and tests relating to the Property.

            (3) All trademarks, logos and other marks, trade or business names,
and all intangible personal property relating to the ownership, development,
use, operation, leases and management of the Property.

            (4) All right, title, and interest of Seller in and to all
transferrable or assignable warranties, representations, guarantees, contract
rights, and miscellaneous rights, if any, with respect to the Property.

            (5) All books, records, and documents of Seller relating to the
Property and Tenant Leases, including without limitation all computer software,
programs, tapes and disks relating to the Property and Tenant Leases.

            (6) All ranges, micro-wave ovens, refrigerators, freezers,
refrigeration/freezer units, dishwashers, clothes washing machines and dryers,
and all other appliances, and all hookups for any of the foregoing or for cable
television.

            (7) All heating, ventilating and air conditioning equipment and
other machinery, whether portable units or fixtures.

            (8) All wall-to-wall carpeting, screens and garbage disposals,
whether personalty or fixtures.

            (9) All certificates of occupancy and all other licenses, permits,
authorizations, consents, certificates and approvals issued by any governmental
authority having jurisdiction over the Property, and all certificates, if any,

<PAGE>

issued by the local board of fire underwriters (or other body exercising similar
functions).


<PAGE>

                                    EXHIBIT C

                                  GROUND LEASES
<PAGE>

                                    EXHIBIT D

                               INSURANCE POLICIES

         (To be completed by Seller within 5 days after the date of this
                               agreement of Sale)
<PAGE>

                                    EXHIBIT E

                           TENANT ESTOPPEL CERTIFICATE

[Buyer] and its assignee

            Re:   ________ Building,
                  [address]
                  (the "Building")

Gentlemen:

            The undersigned ("Tenant") certifies and agrees as follows:

            1. It is the tenant of a portion of the Building known as Suite No.
_____ under the lease dated ______, 19__ (the "Lease"). The Lease has not been
supplemented, modified or amended, and there do not exist any other agreements
concerning the demised premises between the landlord under the Lease and Tenant,
except as set forth below:

             __________________________________________________________________
             __________________________________________________________________
             __________________________________________________________________

            2. The Lease is in full force and effect, and prior to ______, 19__,
the Lease will not be terminated or modified by Tenant without your prior
written consent.

            3. The term of the Lease commenced _______, 19__ and expires
_______, 19__. Tenant has no right to renew or extend the term of the Lease
except as set forth below:

             __________________________________________________________________
             __________________________________________________________________
             __________________________________________________________________

<PAGE>

            4. The current monthly installment of minimum annual rent is
$________. No rent has been paid more than thirty (30) days in advance of its
due date. All rent and other sums payable under the Lease have been paid through
______________, 19__.

            5. Tenant is not entitled to any free rent, rental rebates or other
concessions under the Lease which have not been exhausted, except _____________
_________________________________________.

            6. Tenant has no claim of offset under the Lease or otherwise
against rent or other charges due or to become due under the Lease.

            7. Tenant has accepted possession of the premises demised under the
Lease; all improvements or other work required by the terms of the Lease to be
performed by the landlord have been completed; the rentable area of the demised
premises is ______ square feet.

            8. The landlord is not in default under the Lease, and no event has
occurred which with the giving of notice or passage of time, or both,
constitutes a default by the landlord under the Lease.

            9. Tenant is not in default under the Lease, and no event has
occurred which with the giving of notice or passage of time, or both,
constitutes a default by Tenant under the Lease.

            10. Tenant has not assigned the Lease or any interest therein or
subleased any portion of the demised premises.

            12. The amount of the security deposit held by the landlord under
the Lease is $_____________.

            This Certificate shall inure to the benefit of you, your heirs,
legal representatives, successors and assigns, and shall be binding upon Tenant
and Tenant's heirs, legal representatives, successors and assigns.

            If any statement in this certificate shall become untrue, Tenant
shall immediately give to you written notice of such occurrence.

<PAGE>

            By executing this Certificate, the signatory represents that he/she
is duly authorized to execute this Certificate on behalf of Tenant and legally
bind Tenant.

                                     TENANT:



                                     By: _________________________________
                                          Name:
                                          Title:


Dated: _______________________, 19__


                                      3
<PAGE>

                                    EXHIBIT F

            A written statement addressed to Buyer from the Authority dated as
of a date no more than ten (10) days prior to the Closing Date, setting forth:

                  (1) the last date to which Base Rent and Additional Rent have
been paid,

                  (2) the nature and amount of the moneys then on deposit with
the Authority for the payment of taxes and insurance premiums,

                  (3) consent by the Authority to the assignment of the Ground
Leases to Buyer and confirmation that such conveyance will not constitute an
event of default under the Ground Leases, and that Seller is released of its
obligations under the Ground Leases, and confirmation that the Buyer has or will
personally assume the obligations under the Ground Leases,

                  (4) confirmation by the Authority that the representations and
warranties of Seller in Section 8(w) are true and correct, and

                  (6) confirmation by the Authority that no act, omission or
occurrence after Closing by or in connection with Seller or by or in connection
with any party who has heretofore guaranteed the obligations under the Ground
Leases nor any default under any such guarantee will constitute a default under
the Ground Leases.

<PAGE>

                                    EXHIBIT G

                  ASSIGNMENT AND ASSUMPTION OF TENANT LEASES


            THIS ASSIGNMENT made this ___ day of _______________, 19__, by and
between _____________________________, a ___________________________ having an
office at ___________________________________________________ ("Assignor") and
_____________________________, a __________________________ having an office at
_____________________________________________ ("Assignee").

                                    RECITALS

            A. Pursuant to a certain Agreement of Sale and Purchase dated as of
____________, 19__ (the "Agreement of Sale"), Assignor has agreed to sell to
Assignee, upon the terms, provisions and conditions set forth therein, certain
property (hereinafter "Property") located in ___________________________________
on land described on Exhibit A attached to and made a part of this Assignment,
all as more particularly described in the Agreement of Sale.

            B. In connection with the sale and purchase of the Property,
Assignor desires to assign to Assignee all tenant leases encumbering the
Property and Assignee desires to accept said assignment and assume the
obligations of Assignor under said leases upon the terms, covenants and
conditions set forth in this instrument.

            NOW, THEREFORE, in consideration of the purchase price paid by
Assignee to Assignor for the Property, and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
Assignor and Assignee covenant and agree as follows:

             1. Assignment Assignor hereby assigns, transfers and sets over unto
Assignee all of Assignor's right, title and interest in and to (a) the leases
set forth on Exhibit B attached to and made a part of this Assignment and any
other lease,

<PAGE>

license or right of occupancy affecting the Property, together with all
amendments, extensions, renewals and other modifications thereto (the "Tenant
Leases"), (b) rents, additional rents, fees not to include the traffic impact
fee previously posted by the Seller, and charges now or hereafter arising
thereunder, and (c) any guarantees of any Tenant Leases, to have and to hold the
same unto Assignee, its successors and assigns.

            2. Right to Assign. Assignor represents and warrants that Assignor
has title to and full right to assign the Tenant Leases, and any and all rents,
income and profits and claims arising thereunder, and any guarantees of any
Tenant Leases.

            3. Assumption. Assignee accepts said assignment and assumes all
obligations on the part of the lessor under the Tenant Leases first arising or
accruing on or after the date of this Assignment.

            4. Indemnification by Assignor. Assignor shall indemnify, defend and
hold Assignee harmless from and against any claim, demand, cause of action,
charge, judgment, damage, liability, cost or expense (including, without
limitation, reasonable attorney's fees and legal costs) (a) arising out of the
Tenant Leases in connection with events occurring prior to the date of this
Assignment, or (b) arising out of any claim by any broker, finder or other
intermediary for any leasing or brokerage commission or other compensation in
connection with any Tenant Lease.

            5. Indemnification by Assignee. Assignee shall indemnify, defend and
hold Assignor harmless from and against any claim, demand, cause of action,
charge, judgment, damage, liability, cost or expense (including, without
limitation, reasonable attorneys' fees and legal costs) (a) arising out of the
Tenant Leases in connection with events occurring on or after the date of this
Assignment (exclusive, however, of events described in clause (c) of Paragraph
4) or (b) arising out of any claim by any tenant arising on or after the date of
this Assignment with respect to its escrow or security or other tenant deposit
but only to the extent of the amount of such deposit and interest thereon
transferred by Assignor to Assignee and not returned to such tenant by Assignee.

<PAGE>

            6. Binding Effect. This Assignment shall be binding upon and inure
to the benefit of Assignor and Assignee and their respective heirs, personal
representatives, successors and assigns.


                                      3
<PAGE>

            IN WITNESS WHEREOF, intending to be legally bound, the parties have
caused this instrument to be executed by their duly authorized representatives
on the day and year first above written.


                                    ASSIGNOR:


                                    ASSIGNEE:


ADD NOTARY AFFIDAVITS


                                      4
<PAGE>

                                    EXHIBIT H

                                FIRPTA AFFIDAVIT

                           Form for Entity Transferor


            Section 1445 of the Internal Revenue Code provides that a transferee
of a U.S. real property interest must withhold tax if the transferor is a
foreign person. To inform the transferee that withholding of tax is not required
upon the disposition of a U.S. real property interest by _________________
(Transferor), the undersigned hereby certifies the following on behalf of
Transferor:

            1. Transferor is not a foreign corporation, foreign partnership,
foreign trust, or foreign estate (as those terms are defined in the Internal
Revenue Code and Income Tax Regulations);

            2. Transferor's U.S. taxpayer identification number is ; and

            3. Transferor's office address is:

            ___________________________________
            ___________________________________
            ____________________________________.

Transferor understands that the above information may be disclosed to the
Internal Revenue Service by the transferee and that any false statement
contained herein could be punished by fine, imprisonment, or both.

            Under penalties of perjury, I declare that I have examined this
instrument and to the best of my knowledge and belief it is true, correct, and
complete, and I further declare that I have authority to sign this document on
behalf of Transferor.


---------------------------------     ------------------------------------
                                      Name:
                                      Title:


<PAGE>

Dated: _____________________________

<PAGE>

                                                         Exhibit 10(ad) Amend. 1


               FIRST AMENDMENT TO AGREEMENT OF SALE AND PURCHASE

            THIS FIRST AMENDMENT TO AGREEMENT OF SALE AND PURCHASE is made as of
the 23rd day of September, 1997 by and between GROUP THREE PROPERTIES, INC., a
Pennsylvania corporation ("Seller") and PENN SQUARE PROPERTIES, INC., a
Pennsylvania corporation, or its assignee or nominee ("Buyer").

                             W I T N E S S E T H:

            Seller and Buyer are parties to an Agreement of Sale and Purchase
dated the 13th day of August, 1997 with respect to certain real property situate
in the Township of Bern, Berks County, Commonwealth of Pennsylvania (the
"Agreement of Sale").

            Terms which are defined in the Agreement of Sale shall have the same
meaning when used in this First Amendment.

            Seller and Buyer desire to enter into this Agreement to extend the
expiration date of the Inspection Period.

            NOW, THEREFORE, Seller and Buyer, each intending legally to bound
hereby, agree as follows:

1. Section 14(c)(i) of the Agreement of Sale is amended to provide that the
Inspection Period shall end on October 10, 1997.

2. Except as modified by the provisions of this First Amendment, the Agreement
of Sale shall remain in effect in accordance with its terms and provision.

            IN WITNESS WHEREOF, the Seller and Buyer have executed this First
Amendment as of the day and year first above written.

                                    SELLER:

                                    GROUP THREE PROPERTIES, INC.


                                    By:   /s/ Frederick Snyder
                                          ------------------------------------
                                                President   Sept. 23, 1997

                                    BUYER:

                                    PENN SQUARE PROPERTIES, INC.


                                    By:   /s/ Jeffrey E. Kelter
                                          ------------------------------------
                                                President   September 23, 1997
<PAGE>

                                                      Exhibit 10 (ad) Amend. 2

              SECOND AMENDMENT TO AGREEMENT OF SALE AND PURCHASE

            THIS SECOND AMENDMENT TO AGREEMENT OF SALE AND PURCHASE is made as
of the 10th day of October, 1997 by and between GROUP THREE PROPERTIES, INC., a
Pennsylvania corporation ("Seller") and PENN SQUARE PROPERTIES, INC., a
Pennsylvania corporation, or its assignee or nominee ("Buyer").

                             W I T N E S S E T H:

            Seller and Buyer are parties to an Agreement of Sale and Purchase
dated the 13th day of August, 1997, as amended, with respect to certain real
property situate in the Township of Bern, Berks County, Commonwealth of
Pennsylvania (the "Agreement of Sale").

            Terms which are defined in the Agreement of Sale shall have the same
meaning when used in this First Amendment.

            Seller and Buyer desire to enter into this Agreement to extend the
expiration date of the Inspection Period.

            NOW, THEREFORE, Seller and Buyer, each intending legally to bound
hereby, agree as follows:

1. The Agreement of Sale is amended to provide that the Closing Date shall be
December 1, 1997 and the Inspection Period shall end on October 20, 1997.

2. Except as modified by the provisions of this Second Amendment, the Agreement
of Sale shall remain in effect in accordance with its terms and provision.

            IN WITNESS WHEREOF, the Seller and Buyer have executed this Second
Amendment as of the day and year first above written.

                                    SELLER:

                                    GROUP THREE PROPERTIES, INC.

                                    By:   /s/ Frederic Snyder,
                                          ------------------------------------
                                                President    October 10, 1997

                                    BUYER:

                                    PENN SQUARE PROPERTIES, INC.

                                    By:   /s/ Jeffrey E. Kelter,
                                          ------------------------------------
                                                President    October 10, 1997
<PAGE>

                                                      Exhibit 10 (ad) Amend. 3

            THIRD AMENDMENT TO AGREEMENT OF SALE AND PURCHASE

            THIS THIRD AMENDMENT TO AGREEMENT OF SALE AND PURCHASE is made as of
the 22nd day of October, 1997 by and between GROUP THREE PROPERTIES, INC., a
Pennsylvania corporation ("Seller") and PENN SQUARE PROPERTIES, INC., a
Pennsylvania corporation, or its assignee or nominee ("Buyer").

                             W I T N E S S E T H:

            Seller and Buyer are parties to an Agreement of Sale and Purchase
dated the 13th day of August, 1997, as amended, with respect to certain real
property situate in the Township of Bern, Berks County, Commonwealth of
Pennsylvania (the "Agreement of Sale").

            Terms which are defined in the Agreement of Sale shall have the same
meaning when used in this Third Amendment.

            NOW, THEREFORE, Seller and Buyer, each intending legally to bound
hereby, agree as follows:

1. The Agreement of Sale is amended to provide that the Inspection Period shall
end on Wednesday, October 29, 1997.


2. Except as modified by the provisions of this Second Amendment, the Agreement
of Sale shall remain in effect in accordance with its terms and provision.

            IN WITNESS WHEREOF, the Seller and Buyer have executed this Third
Amendment as of the day and year first above written.

                                     SELLER:

                                    GROUP THREE PROPERTIES, INC.


                                    By:   /s/ Frederic Snyder
                                          ------------------------------------
                                                President    October 22, 1997

                                     BUYER:

                                    PENN SQUARE PROPERTIES, INC.

                                    By:   /s/ Jeffrey E. Kelter
                                          ------------------------------------
                                                President    October 22, 1997
<PAGE>

                                                        Exhibit 10(ad) Amend 5

               FIFTH AMENDMENT TO AGREEMENT OF SALE AND PURCHASE

            THIS FIFTH AMENDMENT TO AGREEMENT OF SALE AND PURCHASE is made as of
the __ day of December, 1997 by and between GROUP THREE PROPERTIES, INC., a
Pennsylvania corporation ("Seller") and MCBRIDE PROPERTIES, a New Jersey general
partnership ("Buyer").

                             W I T N E S S E T H:

            Seller and Penn Square Properties, Inc. are parties to an Agreement
of Sale and Purchase dated the 13th day of August, 1997, as amended, with
respect to certain real properties situate in the Township in Bern, Berks
County, Commonwealth of Pennsylvania (the "Agreement of Sale").

            All of the buyer?s rights, title and interest in an to the Agreement
of Sale have been assigned to Buyer.

            Terms which are defined in the Agreement of Sale shall have the same
meaning when used in this Fifth Amendment.

            NOW, THEREFORE, Buyer and Seller, each intending to be legally to be
bound hereby, agree as follows:

1. Paragraph 2 of the Agreement of Sale is amended and restated to provide as
follows:

                        "2. Purchase Price. The purchase price (the "Purchase
                        Price") for the Property, subject to adjustments as
                        provided in this Agreement, shall be the following sums
                        allocated as follows, which shall be paid as follows:

                              (a) (i) The sum of Five Million Seven Hundred and
                        Sixty Thousand Dollars ($5,760,000) with respect the

<PAGE>

                                                        Exhibit 10(ad) Amend 5

                        Ground Lease dated October 15,
                        1994 (1057 Arnold Road).


                                    (ii) The sum of Three Million Eight Hundred
                        and Forty Thousand Dollars ($3,840,000) with respect the
                        Ground Lease dated July 1, 1996 (1091 Arnold Road).

                              (b) (i) One Hundred Thousand Dollars ($100,000)
                        shall be paid by Buyer?s check drawn to the order of the
                        Title Company within two (2) business days after the
                        expiration of the Inspection Period. The $100,000 sum
                        referred to in the preceding sentence shall be deemed to
                        be the Deposit with respect to the Ground Lease dated
                        October 15, 1994 (1057 Arnold Road).

                                    (ii) One Hundred Thousand Dollars ($100,000)
                        shall be paid by Buyer?s check drawn to the order of
                        First American Title Insurance Company ("Title Company")
                        within two (2) business days after the expiration of the
                        Inspection Period. The $100,000 sum referred to in the
                        preceding sentence shall be deemed to be the Deposit
                        with respect to the Ground Lease dated July 1, 1996
                        (1091 Arnold Road).

                                    (iii) The term "Deposit" shall mean the
                        aforesaid respective sums of $100,000 each, plus all
                        interest which has accrued thereon. The Deposit shall be
                        held by the Title Company in an interest-bearing account
                        pending consummation of this Agreement.

<PAGE>

                              (c) The balance of the Purchase of the Purchase
                        Price shall be paid at Closing by wire transfer of
                        immediate funds to the account of Seller (which account
                        shall be designated by written notice from Seller to
                        Buyer no later than two (2) business days prior to the
                        Closing Date."

2. Paragraph 4 of the Agreement of Sale is amended to provide that Closing for
the Ground Lease dated July 1, 1996 shall be held on December 19, 1997 and that
Closing for the Ground Lease dated October 15, 1994 shall be held on December
29, 1997.

3. Except as modified by the provisions of this Fifth Amendment, the Agreement
of Sale shall remain in full force and effect in accordance with its terms and
provisions.


                                      3
<PAGE>

            IN WITNESS WHEREOF, the Seller and Buyer have executed this Fifth
Amendment as of the day and year first above written.

                              SELLER:

                              GROUP THREE PROPERTIES, INC.


                              By: /s/ Frederic Snyder
                                  --------------------------
                                          President

                              BUYER:

                              MCBRIDE PROPERTIES

                              By:   American Real Estate Investment, L.P., a
                                    General Partner

                                    By:   American Real Estate Investment
                                          Corporation - General Partner


                                          By:   /s/ Stephen J. Butte
                                                Stephen J. Butte, Vice-President


                                      4