Document:

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                                                                   EXHIBIT 10.14

                AGREEMENT FOR THE PURCHASE AND SALE OF PROPERTY

                      FOR THE AT&T CALL CENTER BUILDINGS
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                AGREEMENT FOR THE PURCHASE AND SALE OF PROPERTY
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     THIS AGREEMENT FOR THE PURCHASE AND SALE OF PROPERTY (the "Agreement"), is
made and entered into as of the 22nd day of June, 2000, by and between OKC REAL
ESTATE INVESTMENTS, INC.., a Delaware corporation ("Seller") and WELLS CAPITAL,
INC., a Georgia corporation ("Purchaser").

                             W I T N E S S E T H:
                             - - - - - - - - - -

     WHEREAS, Seller desires to sell and Purchaser desires to purchase the
Property (as hereinafter defined) subject to the terms and conditions
hereinafter set forth.

     NOW, THEREFORE, for and in consideration of the premises, the mutual
agreements contained herein, the sum of Ten Dollars ($10.00) in hand paid by
Purchaser to Seller at and before the sealing and delivery of these presents and
for other good and valuable consideration, the receipt, adequacy, and
sufficiency which are hereby expressly acknowledged by the parties hereto, the
parties hereto do hereby covenant and agree as follows:

     1.   Purchase and Sale of Property. Subject to and in accordance with the
          -----------------------------
terms and provisions of this Agreement, Seller hereby agrees to sell to
Purchaser and Purchaser hereby agrees to purchase from Seller, the Property,
which term "Property" shall mean and include the following:

          (a) surface rights associated with that tract or parcel of land (the
"Land") located in Oklahoma City, Oklahoma, containing approximately 11 acres
located on Quail Springs Parkway in Oklahoma City, Oklahoma, and being more
particularly described on Exhibit "A" hereto; and
                          -----------

          (b) all rights, privileges, and easements appurtenant to the Land and
owned by Seller, if any, including all water rights, mineral rights, reversions,
or other appurtenances to said Land to the extent owned by Seller, and all
right, title, and interest of Seller, if any, in and to any land lying in the
bed of any street, road, alley, or right-of-way, open or proposed, adjacent to
or abutting the Land; and

          (c) all buildings, structures, and improvements situated on the Land,
including, without limitation, that certain one and two story building
containing approximately 128,500 square feet of leasable space, the parking
areas containing approximately 775 parking spaces and other amenities to be
constructed on the Land and owned by Seller, and all apparatus, built-in
appliances, equipment, pumps, machinery, plumbing, heating, air conditioning,
electrical and other fixtures relating thereto owned by Seller (all of which are
herein collectively referred to as the "Improvements"); and

          (d) all personal property now owned by Seller and located on or to be
located on or in, the Land and Improvements ("Personal Property"), provided that
Seller has advised Purchaser that it does not believe any Personal Property
exists; and

          (e) all of Seller's right, title, and interest, as landlord or lessor,
in and to those certain lease agreements (the "Leases") with AT&T Corp.("AT&T")
and Jordan Associates ("Jordan"), dated January 3, 2000 and March 6, 1998,
respectively, AT&T and Jordan being sometimes referred to herein individually as
a "Tenant" or collectively as the "Tenants"; and
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          (f) all of Seller's right, title, and interest in and to the plans and
specifications with respect to the Improvements and any trademarks, rights of
copyright or third party warranties, or other contract rights related to the
ownership of or use and operation of the Land, Personal Property, or
Improvements, all governmental licenses and permits related to the Land,
Personal Property and/or Improvements, and the following intangibles associated
with the Land, Personal Property, and Improvements: the name of the Improvements
and the logo therefor, if any; and

          (g) all of Seller's right, title and interest in and to the contracts,
if any,  described on Exhibit "B" hereto (the "Contracts"), to the extent the
                      -----------
same survive Closing or require performance after Closing.

     2.   Earnest Money. Within two (2) business days after the full execution
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of this Agreement, Purchaser shall deliver to First American Title Insurance
Company ("Escrow Agent" and "Title Company"), whose offices are at 133 N.W. 8th
Street, Oklahoma City, Oklahoma 73102, ph: #(405)236-2861, Purchaser's check,
payable to Escrow Agent, in the amount of $300,000.00 (the "Earnest Money"),
which Earnest Money shall be held and disbursed by Escrow Agent in accordance
with this Agreement. The Earnest Money shall be paid by Escrow Agent to Seller
at Closing (as hereinafter defined) and shall be applied as a credit to the
Purchase Price (as hereinafter defined), or shall otherwise be paid to Seller or
refunded to Purchaser in accordance with the terms of this Agreement. All
interest and other income from time to time earned on the Earnest Money shall
belong to Purchaser and shall be disbursed to Purchaser at any time or from time
to time as Purchaser shall direct Escrow Agent. In no event shall any such
interest or other income be deemed a part of the Earnest Money.

     3.   Purchase Price. Subject to adjustment and credits as otherwise
          --------------
specified in this Agreement, the purchase price (the "Purchase Price") to be
paid by Purchaser to Seller for the Property shall be FIFTEEN MILLION THREE
HUNDRED THOUSAND AND 00/100 DOLLARS ($15,300,000.00). The Purchase Price shall
be paid by Purchaser to Seller at the Closing (as hereinafter defined) by wire
transfer of immediately available federal funds, subject to prorations,
adjustments and credits as otherwise specified in this Agreement.

     4.   Special Condition to Closing. Within two (2) business days after
          -----------------------------
Purchaser's deposit of the Earnest Money, Seller shall make available to
Purchaser, or Purchaser's agents and representatives, for review and copying,
all of the due diligence materials described in Exhibit "C" hereto.  Purchaser
shall have thirty (30) days from the effective date of this Agreement (the
"Inspection Period") to make investigations, examinations, inspections, market
studies, feasibility studies, lease reviews, and tests relating to the Property
and the operation thereof in order to determine, in Purchaser's sole opinion and
discretion, the suitability of the Property for acquisition by Purchaser.
Purchaser shall have the right to terminate this Agreement at any time prior to
the expiration of the Inspection Period by giving written notice to Seller of
such election to terminate.  In the event Purchaser so elects to terminate this
Agreement, Seller shall be entitled to receive and retain the sum of Twenty-Five
Dollars ($25.00) of the Earnest Money, and the balance of the Earnest Money
shall be promptly refunded by Escrow Agent to Purchaser, whereupon, except as
expressly provided to the contrary in this Agreement, no party hereto shall have
any other or further rights or obligations under this Agreement. Seller
acknowledges that the sum of $25.00 is good and adequate consideration for the
termination rights granted to Purchaser hereunder. In the event Purchaser does

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not terminate this Agreement during the Inspection Period, Purchaser will be
deemed to have approved the title exceptions listed in Exhibit "A"  attached
hereto (the "Permitted Exceptions").

     5.   Purchaser's Inspection and Review Rights. Purchaser and its agents,
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engineers, or representatives, with Seller's reasonable, good faith cooperation,
shall have the privilege of going upon the Property as needed to inspect,
examine, test, and survey the Property at all reasonable times and from time to
time, provided, however, that (i) such activities shall not, without Seller's
prior written consent, damage the Property in any way or disrupt the Tenants in
any way; (ii) such activities shall not interfere with Seller's construction
activities; (iii) all such persons shall comply with reasonable safety
requirements of Seller; and (iv) Seller shall have no liability or obligation to
any of such persons for any injury or loss suffered while said persons are upon
the Property. Purchaser hereby agrees to indemnify Seller and hold Seller
harmless from any liens, claims, liabilities, and damages incurred through the
exercise of such privilege, and Purchaser further agrees to repair any damage to
the Property caused by the exercise of such privilege. The foregoing indemnity
shall survive any termination of this Agreement.

     6.   General Conditions Precedent to Purchaser's Obligations Regarding the
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Closing. In addition to the condition to Purchaser's obligations set forth in
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Paragraph 4 above, the obligations and liabilities of Purchaser hereunder shall
in all respects be conditioned upon the satisfaction of each of the following
conditions, any of which may be waived by written notice from Purchaser to
Seller:

          (a) Seller shall have complied in all material respects with and
otherwise performed in all material respects each of the covenants and
obligations of Seller set forth in this Agreement, as of the date of Closing (as
hereinafter defined).

          (b) All representations and warranties of Seller as set forth in this
Agreement shall be true and correct in all material respects as of the date of
Closing.

          (c) There shall have been no material adverse change to the title to
the Property which has not been cured and the Title Company (as hereinafter
defined) shall have issued the Title Commitment (as hereinafter defined) on the
Land and Improvements with full extended coverage without exceptions (other than
the Permitted Exceptions) and the Title Company shall be prepared to issue to
Purchaser upon the Closing a fee simple owner's title insurance policy on the
Land and Improvements pursuant to such Title Commitment with the endorsements in
the form attached to the Title Commitment or otherwise described in Exhibit "C".

          (d) Purchaser shall have received Tenant Estoppel Certificates in
substantially the form of Exhibit "D" (the "Tenant Estoppel Certificates"), duly
executed by AT&T and Jordan at least five (5) days prior to the date of Closing.

          (e) Seller shall have caused the project Architect(s) to execute and
deliver to Purchaser a certificate (the "Architect's Certificate") in the form
attached hereto as Exhibit "E".

          (f) Seller shall have delivered to Purchaser either a Certificate of
Occupancy (as contemplated by the Lease with AT&T) or a certificate from the
City of Oklahoma City stating that

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the Improvements constructed on the Property are in compliance with all
applicable zoning laws, rules and regulations.

          (g) Seller shall have delivered to Purchaser an "as built" survey of
the Land and the Improvements (the "As-built Survey") dated not more than thirty
(30) days prior to the Closing certified to Purchaser and to the Title Company
showing the boundaries and the legal description of the Land, which survey shall
be made in compliance with the "Minimum Standard Detail Requirements for Land
Title Surveys" established by the ALTA/ACSM and currently in effect, including
the items listed in Table A thereto, and shall contain and disclose the matters
and information set forth in the preliminary survey delivered to Purchaser
pursuant to Section 4 of this Agreement.  The As-built Survey shall disclose no
encroachments of improvements from or upon adjoining properties, shall show the
availability of all utility services at the perimeter of the Land, and shall
otherwise be in form and content sufficient to enable the Title Company to issue
its standard form of survey modification endorsement modifying the general
exception for matters of survey.  The costs of each survey delivered by Seller
pursuant hereto shall be borne entirely by Seller.

     7.   Representations and Warranties of Seller. Seller hereby makes the
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following representations and warranties to Purchaser, each of which shall be
deemed material:

          (a) Leases. Attached hereto as Exhibit "F"  are true and accurate
              ------                     -----------
copies of the only leases in effect relating to the Property, together with all
modifications and amendments to such leases (such leases, as modified and
amended, being herein referred to as the "Leases"). Seller is the "landlord"
under the Leases and owns unencumbered legal and beneficial title to the Leases
and the rents and other income thereunder, subject only to the collateral
assignment of the Leases and the rents thereunder in favor of the holder of an
existing mortgage or deed of trust encumbering the Property ("Mortgagee"), which
mortgage or deed of trust shall be canceled and satisfied by Seller at the
Closing.

          (b) Leases - Assignment. To the best of Seller's knowledge, no tenant
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has assigned its interest or sublet any portion of the premises leased to the
Tenant under the Leases.

          (c) Leases - Default.(i) Seller has not received any notice of
              ----------------
termination or default under the Leases,(ii) to the best of Seller's knowledge,
there are no existing or uncured defaults by Seller or by the Tenants under the
Leases, (iii) to the best of Seller's knowledge, there are no events which with
the passage of time or notice, or both, would constitute a default by Seller or
by the Tenants, and Seller has complied with each and every undertaking,
covenant, and obligation of Seller under the Leases where noncompliance could
reasonably be expected to have a material adverse effect on the Leases, and (iv)
no Tenant has asserted any defense, set-off, or counterclaim with respect to its
tenancy or its obligation to pay rent, additional rent, or other charges
pursuant to the Leases.

          (d) Leases - Rents and Special Consideration. No Tenant:(i) has
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prepaid rent for more than the current month under  its Lease, (ii) has received
and is entitled to receive any rent concession in connection with its tenancy
under its Lease other than as described in its Lease, (iii) except as described
in the Leases, is entitled to any special work (not performed prior to the
Closing Date),or consideration (not yet given) in connection with its tenancy
under the Leases, and (iv) has

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any purchase option, or other ownership interest in or to the Property, except
for the Tenant's tenancy as evidenced by the express terms of the Leases.

          (e) Leases - Commissions. All commissions payable under, relating to,
              --------------------
or as a result of the Leases will be cashed-out and paid and satisfied in full
by Seller at or prior to Closing.

          (f) No Other Agreements.  Other than the Leases, the Contracts and the
              -------------------
Permitted Exceptions, there are no leases, service contracts, management
agreements, or other agreements or instruments in force and effect, oral or
written, to which Seller is a party and that grant to any person whomsoever or
any entity whatsoever any right, title, interest or benefit in or to all or any
part of the Property or any rights relating to the use, operation, management,
maintenance, or repair of all or any part of the Property.

          (g) No Litigation. There are no actions, suits, or proceedings
              -------------
pending, or, to the best of Seller's knowledge, threatened by any organization,
person, individual, or governmental agency against Seller with respect to the
Property or against the Property that could reasonably be expected to have a
material adverse effect on the Property or the Seller's ability to perform its
obligations hereunder, nor does Seller know of any basis for such action.
Seller has no knowledge of any pending or threatened application for changes in
the zoning applicable to the Property or any portion thereof.

          (h) Condemnation. Seller has no knowledge of any pending condemnation
              ------------
or other taking by eminent domain of the Property or any portion thereof and, to
the best of Seller's knowledge, there are no pending or threatened condemnation
or eminent domain proceedings (or proceedings in the nature or in lieu thereof)
affecting the Property or any portion thereof or its use.

          (i) Access. To the best of Seller's knowledge, there are no pending or
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threatened proceedings that could have the effect of impairing or restricting
access between the Property and the adjacent public roads.

          (j) No Assessments. To the best of Seller's knowledge, no assessments
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have been made against the Property that are unpaid, whether or not they have
become liens.

          (k) Violations. To the best of Seller's knowledge, there are no
              ----------
violations of law, municipal or county ordinances, or other legal requirements
with respect to the Property.

          (l) Utilities. All utilities and utility equipment, facilities and
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services necessary for the operation of the Improvements as contemplated by the
Plans and Specifications (as elsewhere defined herein) will be installed and
connected pursuant to valid permits and will meet the requirements of Tenant
pursuant to the Lease, including water, sanitary sewer, storm sewer and
electricity.

          (m) Tax Returns. To the best of Seller's knowledge, all property tax
              -----------
returns required be filed by Seller relating to the Property under any law,
ordinance, rule, regulation, order, or requirement of any governmental authority
have been truthfully, correctly, and timely filed.

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          (n) Bankruptcy. Seller is "solvent" as said term is defined by
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bankruptcy law and has not made a general assignment for the benefit of
creditors nor been adjudicated a bankrupt or insolvent, nor has a receiver,
liquidator, or trustee for any of Seller's properties (including the Property)
been appointed or a petition filed by or against Seller for bankruptcy,
reorganization, or arrangement pursuant to the Federal Bankruptcy Act or any
similar Federal or state statute, or any proceeding instituted for the
dissolution or liquidation of Seller.

          (o) Pre-existing Right to Acquire. Other than Purchaser, no person or
              -----------------------------
entity has any right or option to acquire the Property or any portion thereof
which will have any force or effect after the execution of this Agreement.

          (p) Effect of Certification. To the best of Seller's knowledge,
              -----------------------
neither this Agreement nor the transactions contemplated herein will constitute
a breach or violation of, or default under, or will be modified, restricted, or
precluded by the Leases or the Permitted Exceptions.

          (q) Authorization. Seller is a duly organized and validly existing
              -------------
corporation under the laws of the State of Delaware, and is qualified to do
business in the State of Oklahoma. This Agreement has been duly authorized and
executed on behalf of Seller and constitutes the valid and binding agreement of
Seller, enforceable in accordance with its terms, and all necessary action on
the part of Seller to authorize the transactions herein contemplated has been
taken, and no further action is necessary for such purpose.

          (r) Seller Not a Foreign Person. Seller is not a "foreign person"
              ---------------------------
which would subject Purchaser to the withholding tax provisions of Section 1445
of the Internal Revenue Code of 1986, as amended.

          (s) Plans and Specifications. To the best of Seller's knowledge,
              ------------------------
attached hereto as Exhibit "G" is a complete list (to date) of all plans and
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specifications (the "Plans and Specifications") relating to the additional
Improvements contemplated by the Lease with AT&T, including all change orders,
shop drawings, bulletins and other documents varying or interpreting the
architectural or other drawings. The Improvements, when completed in accordance
with the Plans and Specifications, and when fully equipped with all of the
building equipment will be ready for use and fulfill the Seller's obligations
under the Lease with AT&T. Seller shall cause all amendments to the Plans and
Specifications to be prepared in compliance in all material respects with (i)
the requirements and standards set forth in the Lease with AT&T, (ii) all
applicable governmental requirements, and (iii) all private covenants,
conditions and restrictions of record that encumber all or any part of the Land.
Seller shall not amend the Plans and Specifications in any manner which would
have a material adverse effect on the value of the Property, or which would
violate its obligations under the Lease with AT&T, without the prior written
consent of Purchaser, except as otherwise expressly permitted herein.
Purchaser's approval of the Plans and Specifications shall not constitute, and
shall not be deemed to constitute, an acknowledgment by Purchaser that the Plans
and Specifications comply with the requirements of the immediately preceding
sentence, nor shall Purchaser's approval of the Plans and Specifications in any
way constitute a waiver of (or diminish Seller's obligation to satisfy fully)
the requirements of the immediately preceding sentence.

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          (t) Approvals. The requirements of all covenants, conditions and
              ---------
restrictions of record relating to the development or construction of the
additional Improvements contemplated by the Lease with AT&T, including all
covenants requiring consent from any third party, have been, or on the Closing
Date will be, fully satisfied and complied with in all material respects.

          (u) Contracts. Attached hereto as Exhibit "B" is a complete list and
              ---------                     -----------
description of all existing contracts and agreements to which Seller is a party
relating to or affecting the Land or the development or construction of the
additional Improvements contemplated by the Lease with AT&T, including the
contracts or agreements with the Architect, General Contractor, any construction
manager, other professionals or specialists, or utility companies. All such
contracts or agreements listed on said Exhibit "B" are in full force and effect.
                                       -----------
To Seller's knowledge, neither party to any such contract is in default
thereunder and no event has occurred which, with the mere passage of time or the
delivery of notice or both, would constitute a default or breach thereunder.

          (v) Inducements. To the best of Seller's knowledge, (i) there are no
              -----------
donations of monies or land or payments (other than general real estate taxes)
for schools, parks, fire departments or any other public facilities which are or
will be required to be made by an owner of the Improvements, and (ii) there are
no obligations burdening the Improvements created by any so-called "recapture
agreement" involving refund for sewer or water extension or other improvement to
any sewer or water systems, oversizing utility, lighting or like expense or
charge for work or services done upon or relating to the Improvements which will
bind the Purchaser or the Improvements from and after the closing.

          (w) Hazardous Substances.  To the best of Seller's knowledge, except
              --------------------
as may be disclosed in the Phase I Environmental Assessment(s) described on
Exhibit "C" hereto or thew Leases,  (i) no "hazardous substances",as that term
-----------
is defined in the Comprehensive Environmental Response, Compensation and
Liability Act of 1980, as amended, 42 U.S.C. Section 9601, et. seq., the
                                                           --  ---
Resource Conservation and Recovery Act, as amended, 42 U.S.C. Section 6901 et.
                                                                           --
seq., and the rules and regulations promulgated pursuant to these acts, any so-
---
called "super-fund" or "super-lien" laws or any applicable state or local laws,
nor any other pollutants, toxic materials, or contaminants have been or shall
prior to Closing be discharged, disbursed, released, stored, treated, generated,
disposed of, or allowed to escape on the Property, (ii) no asbestos or asbestos
containing materials have been installed, used, incorporated into, or disposed
of on the Property, (iii) no polychlorinated biphenyls are located on or in the
Property, in the form of electrical transformers, fluorescent light fixtures
with ballasts, cooling oils, or any other device or form, (iv) no underground
storage tanks are located on the Property or were located on the Property and
subsequently removed or filled, (v) no investigation, administrative order,
consent order and agreement, litigation, or settlement with respect to Hazardous
Substances is proposed, threatened, anticipated or in existence with respect to
the Property, and (vi) the Property has not previously been used as a landfill,
cemetery, or as a dump for garbage or refuse.

          At Closing, Seller shall represent and warrant to Purchaser that all
representations and warranties of Seller in this Section 7 remain true and
correct as of the date of the Closing, except for any changes in any such
representations or warranties that occur and are disclosed by Seller to
Purchaser in writing at any time and from time to time prior to Closing and
within a reasonable period of time after their occurrence, which disclosures
shall thereafter be updated by Seller to the date of

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Closing. Each and all of the express warranties, made and given by Seller to
Purchaser in this Section 7 shall survive the execution and delivery of the
Warranty Deed by Seller to Purchaser for one year.

     8.   Seller's Additional Covenants. Seller does hereby further covenant and
          -----------------------------
agree as follows:

          (a) Operation of Property.  Seller hereby covenants that, from the
              ---------------------
date of this Agreement up to and including the date of Closing, Seller shall:
(i) not negotiate with any third party respecting the sale of the Property or
any interest therein, (ii) not modify, amend, or terminate the Leases (excluding
amendments necessary in the ordinary course of business) or enter into any new
leases, (iii) not grant or otherwise create or consent to the creation of any
easement, restriction, lien, assessment, or encumbrance respecting the Property,
other than liens in favor of Mortgagee and utility easements or ingress/egress
easements necessary for the Property's development, (iv) cause the Property to
be operated, maintained, and repaired in the same manner as the Property is
currently being operated, maintained, and repaired, subject to operational
modifications required by the AT&T expansion, and (v) not enter into any
service, management or maintenance contract which will survive Closing, without
the consent of Purchaser.

          (b) Preservation of Leases. Seller shall, from and after the date of
              ----------------------
this Agreement to the date of Closing, use its good faith efforts to perform and
discharge all of the duties and obligations and shall otherwise comply with
every material covenant and agreement of the landlord under the Leases, at
Seller's expense, in the manner and within the time limits required thereunder.
Furthermore, Seller shall, for the same period of time, use diligent and good
faith efforts to cause the Tenants under the Leases to perform all of their
respective duties and obligations and otherwise comply with each and every one
of their covenants and agreements under such Leases and shall take such actions
as are reasonably necessary to enforce the terms and provisions of the Leases.

          (c) Insurance. From and after the date of this Agreement to the date
              ---------
and time of Closing, Seller shall, at its expense,  cause to be maintained in
full force and effect the insurance coverage described in Exhibit "H".
                                                          -----------

          (d) CAD Disk. On or before the Closing Date, Seller shall deliver to
              --------
Purchaser as built drawings depicting the Improvements as constructed, such
drawings to be delivered on a CAD disk.

          (e) Assignment of Contracts. With respect to the Contracts specified
              -----------------------
on Exhibit "B" which are being assigned to Purchaser, there shall have been
delivered to Purchaser, at or prior to the Closing, written instruments from the
contracting parties whereby they consent to the assignment of the contract and
any related warranties and guaranties.

          (f) Covenant to Satisfy Conditions; Effect of Failure to Satisfy.
              ------------------------------------------------------------
Seller hereby agrees to use commercially reasonable efforts to cause each of the
conditions precedent to the obligations of Purchaser to be fully satisfied,
performed and discharged, on and as of the Closing Date.

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          (g) Completion of Construction. Seller agrees that it shall, with
              --------------------------
diligence and continuity, cause the additional Improvements contemplated by the
Lease with AT&T to be completed in accordance with the Plans and Specifications
and the Lease with AT&T as evidenced by the Architect's Certificate (the
"Completion of Construction").

          (h) Action with Respect to the Property. Seller shall not in any
              -----------------------------------
manner sell, convey, assign, transfer or encumber the Improvements or the Leases
or any part thereof or interest therein (except to secure, refinance or extend
any existing construction loan which shall be paid off on or before Closing), or
otherwise dispose of the Improvements or the Leases, or any part thereof or
interest therein, or alter or amend the zoning classification of the
Improvements, or otherwise perform any act or deed which shall materially
diminish, encumber or adversely affect Seller's rights in and to the
Improvements, or prevent Seller from performing fully its obligations hereunder,
nor enter into any agreement to do so.

          (i) Books and Records. Seller shall maintain, or cause to be
              -----------------
maintained, complete books and records with respect to the Improvements.  At all
reasonable times, and upon prior notice, Purchaser shall have the right, from
time to time upon request therefor, to inspect and make copies of the books and
records of Seller relating to the construction of the Improvements and the
operation of the Property, including those described on Exhibit "C" hereto, and
Seller agrees to cause the same to be made available to Purchaser for such
purpose during regular business hours at the Seller's principal offices or, at
Seller's option after notice to Purchaser, at or in the vicinity of the
Improvements.

          (j) Purchaser's Access. Seller shall grant to Purchaser and its
              ------------------
engineers, architects and other agents or representatives of Purchaser, access
to the Improvements for the purpose of making a physical inspection thereof, and
each of its component parts; provided, however, that (i) inspections shall not
disrupt the Tenants in any way; (ii) inspections shall not interfere with
Seller's construction activities; (iii) all such persons shall comply with
reasonable safety requirements of Seller; and (iv) and Seller shall have no
liability or obligation to any of such persons for any injury or loss suffered
while said persons are upon the Improvements.  Purchaser shall not damage the
Property in any manner without Seller's prior written consent, and if such
consent is given, Purchaser shall restore the Land to its condition existing
immediately before Purchaser's entry upon the Land, and Purchaser shall
indemnify and defend Seller against and hold Seller harmless from all claims,
demands, liabilities, losses, damages, costs and expenses, including reasonable
attorneys' fees and disbursements (collectively, "Claims"), in any manner
                                                  ------
arising from any such inspections; provided, however, Purchaser's foregoing
obligations shall not include any obligation or duty with respect to Claims
(including Claims that the Land has declined in value) arising out of, resulting
from or incurred in connection with (i) the discovery or presence of any
Hazardous Substances on the Land not brought on the Land by Purchaser (or any of
its representatives or agents) or the Release (other than by Purchaser or its
representatives or agents) of any Hazardous Substances on the Land, or (ii) the
results, findings, tests or analyses of Purchaser's environmental investigation
of the Land.  The foregoing indemnity shall survive any termination of this
Agreement.

          (k)  Progress Reports.  Seller shall report to Purchaser in writing,
               ----------------
from time to time, but not less frequently than monthly, as to the progress of
construction of the additional Improvements to be constructed pursuant to the
Lease with AT&T (such reports to include, without

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limitation, an updated construction schedule and photographs of construction
progress to date).Seller shall report to Purchaser in writing any construction
defects or material deviations from the Plans and Specifications promptly upon
Seller becoming aware of same, which notice shall describe the nature of such
defect or deviation in reasonable detail.

          (l)  Default Notices.  Seller shall deliver or cause to be delivered
               ---------------
to Purchaser, promptly upon receipt thereof by Seller, copies of any written
notices of default, or the occurrence of any event which could result in a
default, under the Leases or any construction loan or mortgage or the
construction contract(s), now or at any time hereafter in effect with respect to
the Improvements, and shall report to Purchaser, from time to time, the status
of any alleged default thereunder. Seller shall advise Purchaser in writing,
promptly upon obtaining actual knowledge of the occurrence of any event or
circumstance which constitutes a breach of any of the representations or
warranties or covenants of Seller herein contained, which notice shall describe
the nature of such event or circumstance in reasonable detail.  Seller agrees
that it will use commercially reasonable efforts at all times to correct any
such event or circumstance within Seller's reasonable control and, to the extent
the same is within the reasonable control of Seller, to cause all
representations and warranties of Seller herein contained to be true and correct
on and as of the Closing Date, and to cause Seller to be in compliance with its
covenants and obligations hereunder. Seller shall advise Purchaser promptly in
writing of the receipt by Seller, of notice of:  (i) the institution or
threatened institution of any judicial, quasi-judicial or administrative inquiry
or proceeding with respect to the Improvements; (ii) any notice of violation
issued by any governmental or quasi-governmental authority with respect to the
Improvements, (iii) any proposed special assessments, or (iv) any defects or
inadequacies in the Improvements or any part thereof issued by any insurance
company or fire rating bureau.

          (o)  Warranties.  With respect to any contractor warranties or
               ----------
guaranties relating to the Expansion Space (as that term is defined in the AT&T
Lease) which are assigned, or required to be assigned, to Purchaser pursuant to
Section 1(f), or otherwise, and which, by their terms or otherwise expire,
terminate or lapse at any time prior to the date which is one year following
Completion of Construction (the "Warranty Date"), Seller hereby assumes and
agrees to pay, perform and discharge all of the liabilities and obligations of
the various contractors as above provided for the period from the date of
expiration thereof to and including the Warranty Date, it being the intention of
the parties hereto that such guarantees or warranties which have expired,
terminated or lapsed prior to the Warranty Date shall be extended by the
provisions of this Subsection and shall be the liability and obligation of
Seller during such extended period.

          (p)  Punch List Work.  The parties acknowledge that certain portions
               ---------------
of the building and the building equipment constituting a part of the
Improvements may not have been finally completed on the Closing Date.
Accordingly, the Architect shall determine the amount (the "Punch List Amount")
as may be necessary to (i) satisfactorily complete any items of construction, or
to provide any items of building equipment, required by the Plans and
Specifications which, while substantially complete, have not been finally
completed or provided on the Closing Date, other than the Seasonal Punch List
Work referred to below (the "Regular Punch List Work"); (ii) satisfactorily
complete any landscaping required by the Plans and Specifications which cannot
then be completed on account of weather or the season (the "Seasonal Punch List
Work"); and (iii) correct any material defects ("Defects") in the design or
construction of the Improvements or the materials incorporated

                                      10
<PAGE>

therein (the Defects, together with the Regular Punch List Work and the Seasonal
Punch List Work being collectively called the "Punch List Work"). If the Punch
List Amount exceeds One Hundred Thousand Dollars ($100,000), the Closing may, at
the option of Purchaser, be deferred until such time as a sufficient amount of
work shall have been performed with respect to the Seasonal Punch List Work, the
Defects or the Regular Punch List Work so that the Punch List Amount shall be
reduced to an amount within the limit prescribed. As expeditiously and prudently
as possible after the Closing Date, Seller shall complete, or cause to be
completed, all of the Punch List Work. Seller's covenant to complete the Punch
List Work shall survive the Closing, and any amounts owed by AT&T under its
Lease for tenant improvements shall be payable to Seller notwithstanding the
Closing.

          9.  Closing. Provided that all of the conditions set forth in Section
              -------
6 of this Agreement are theretofore fully satisfied or performed, it being fully
understood and agreed, however, that Purchaser may expressly waive in writing,
at or prior to Closing, any conditions that are unsatisfied or unperformed at
such time, the consummation of the sale by Seller and purchase by Purchaser of
the Property (herein referred to as the "Closing") shall be held at 11:00 a.m.,
local time, on  the fifth (5th) business day following Completion of
Construction, at the offices of Title Company, or at such earlier time as shall
be designated by Purchaser in a written notice to Seller not less than two (2)
business days prior to Closing. The Closing shall take place through an escrow
established with the Title Company (the "Escrow") by means of a so-called New
York style closing, with the concurrent delivery of Seller's deed and other
documents of title, the delivery of the Title Policy (or marked title
commitment) described below, and the payment of the Purchase Price.

          10. Seller's Closing Documents. For and in consideration of, and as a
              --------------------------
condition precedent to, Purchaser's delivery to Seller of the Purchase Price
described in Paragraph 3 hereof, Seller shall obtain or execute, at Seller's
expense, and deliver to Purchaser at Closing the following documents (all of
which shall be duly executed, acknowledged, and notarized where required and
shall survive the Closing):

               (a)  Special Warranty Deed. A Special Warranty Deed conveying to
                    ---------------------
Purchaser insurable fee simple title to the Land and Improvements, subject to
the Permitted Exceptions, together with any appurtenant rights described in
Section 1(b) of this Agreement. The legal description set forth in the Deed
shall be as set forth on Exhibit "A". In the event the legal description in the
                         -----------
"As-built Survey" shall differ from the legal description set forth on Exhibit
"A", Seller shall also execute and deliver a quitclaim deed conveying title by
the legal description based upon such survey;

               (b)  Bill of Sale. A Bill of Sale conveying to Purchaser
                    ------------
marketable title to the Personal Property, if any, in the form and substance of
Exhibit "I";
-----------

               (c)  Blanket Transfer. A Blanket Transfer and Assignment in the
                    ----------------
form and substance of Exhibit "J";
                      -----------

               (d)  Assignment and Assumption of Leases. An Assignment and
                    -----------------------------------
Assumption of Leases in the form and substance of Exhibit "K",assigning to
                                                  -----------
Purchaser all of Seller's right, title, and interest in and to the Leases and
the rents thereunder and pursuant to which Purchaser shall assume all
obligations under the Leases accruing after the date of said assignment;

                                      11

<PAGE>

               (e)  Seller's Affidavit. A customary seller's affidavit in the
                    ------------------
form required by the Title Company;

               (f)  FIRPTA Certificate. A FIRPTA Certificate in such form as
                    ------------------
Purchaser shall reasonably approve;

               (g)  Certificates of Occupancy. The original Certificates of
                    -------------------------
occupancy for all space within the Improvements;

               (h)  Marked Title Commitment. The Title Commitment, marked to
                    -----------------------
change the effective date thereof through the date and time of recording the
Special Warranty Deed from Seller to Purchaser, to reflect that Purchaser is
vested with the fee simple title to the Land and the Improvements, and to
reflect that all requirements for the issuance of the final title policy
pursuant to such Title Commitment have been satisfied;

               (i)  Keys and Records.  The original tenant files and other
                    ----------------
books and records in Seller's possession relating to the operation of the
 Property;

               (j)  Tenant Notice. Notice from Seller to the Tenants of the
                    -------------
sale of the Property to Purchaser in such form as Purchaser shall reasonably
 approve;

               (k)  Settlement Statement. A settlement statement setting forth
                    --------------------
the amounts paid by or on behalf of and/or credited to each of Purchaser and
Seller pursuant to this Agreement; and

               (l)  Other Documents. Such other documents as shall be reasonably
                    ---------------
required by Purchaser's counsel.

          11.  Purchaser's Closing Documents. Purchaser shall obtain or execute
               -----------------------------
and deliver to Seller at Closing the following documents, all of which shall be
duly executed and acknowledged where required and shall survive the Closing:

               (a)  Blanket Transfer. The Blanket Transfer and Assignment;
                    ----------------

               (b)  Assignment and Assumption of Lease. The Assignment and
                    ----------------------------------
Assumption of Lease;

               (c)  Settlement Statement. A settlement statement setting forth
                    --------------------
the amounts paid by or on behalf of and/or credited to each of Purchaser and
Seller pursuant to this Agreement; and

               (d)  Other Documents. Such other documents as shall be reasonably
                    ---------------
required by Seller's counsel.

          12.  Closing Costs. Seller shall pay the cost of the Title Commitment
               -------------
(including endorsements), including the cost of the examination of title to the
Property made in connection therewith, the premium (including endorsements) for
the owner's policy of title insurance issued

                                      12
<PAGE>

pursuant thereto, the cost of any transfer or documentary tax imposed by any
jurisdiction in which the Property is located, the cost of the As-built Survey,
the attorneys' fees of Seller, and all other costs and expenses incurred by
Seller in closing and consummating the purchase and sale of the Property
pursuant hereto. Purchaser shall pay the attorneys' fees of Purchaser, and all
other costs and expenses incurred by Purchaser in closing and consummating the
purchase and sale of the Property pursuant hereto. Each party shall pay one-half
of any escrow fees.

          13.  Prorations.  The following items shall be prorated and/or
               ----------
credited between Seller and Purchaser as of Midnight preceding the date of
Closing:

               (a)  Rents. Rents, additional rents, and other income of the
                    -----
Property (other than security deposits, which shall be assigned and paid over to
Purchaser) collected by Seller from Tenant for the month of Closing. Purchaser
shall also receive a credit against the Purchase Price payable by Purchaser to
Seller at Closing for any rents or other sums (not including security deposits)
prepaid by Tenant to Seller for any period following the month of Closing, or
otherwise.

               (b)  Property Taxes. Except for such taxes which are the
                    --------------
responsibility of Tenant, City, state, county, and school district ad valorem
taxes based on the ad valorem tax bills for the Property, if then available, or
if not, then on the basis of the latest available tax figures and information.
Should such proration be based on such latest available tax figures and
information and prove to be inaccurate upon receipt of the ad valorem tax bills
for the Property for the year of Closing, either Seller or Purchaser, as the
case may be, may demand at any time after Closing a payment from the other
correcting such malapportionment. In addition, if after Closing there is an
adjustment or reassessment by any governmental authority with respect to, or
affecting, any ad valorem taxes for the Property for the year of Closing or any
prior year, any additional tax payment for the Property required to be paid with
respect to the year of Closing shall be prorated between Purchaser and Seller
and any such additional tax payment for the Property for any year prior to the
year of Closing shall be paid by Seller. This agreement shall expressly survive
the Closing.

               (c)  Utility Charges. Except for utilities which are the
                    ---------------
responsibility of Tenant, Seller shall pay all utility bills received prior to
Closing and shall be responsible for utilities furnished to the Property prior
to Closing. Purchaser shall be responsible for the payment of all bills for
utilities furnished to the Property subsequent to the Closing. Seller and
Purchaser hereby agree to prorate and pay their respective shares of all utility
bills received subsequent to Closing, which agreement shall survive Closing.

          The information to be furnished by Seller on which the computation of
prorations is based shall be true, correct and complete in all respects.

          14.  Purchaser's Default. In the event of default by Purchaser under
               -------------------
the terms of this Agreement, Seller's sole and exclusive remedy shall be to
receive the Earnest Money as liquidated damages and thereafter the parties
hereto shall have no further rights or obligations hereunder whatsoever. It is
hereby agreed that Seller's damages will be difficult to ascertain and that the
Earnest Money constitutes a reasonable liquidation thereof and is intended not
as a penalty, but as fully liquidated damages. Seller agrees that in the event
of default by Purchaser, it shall not initiate any

                                      13
<PAGE>

proceeding to recover damages from Purchaser, but shall limit its recovery to
the retention of the Earnest Money.

        Seller's Initial       SF          Purchaser's Initials      DPW
                         -------------                          -------------

          15.  Seller's Default. In the event of default by Seller under the
               ----------------
terms of this Agreement which is not cured within thirty (30) days after Seller
receives written notice thereof from Purchaser, at Purchaser's option: (i) if
any such defects or objections consist of (A) mortgages, deeds of trust, deeds
to secure debt, and (B) taxes, mechanic's or materialman's liens, or other such
monetary encumbrances, and such defects are not bonded and/or otherwise resolved
to the satisfaction of the Title Company, then in either such event, the Title
Company shall withhold from Seller's proceeds at Closing such amounts as may be
necessary to cure such defects or objections, and upon such curing, the Closing
hereof shall proceed in accordance with the terms of this Agreement; or (ii)
Purchaser shall have the right to terminate this Agreement by giving written
notice of such termination to Seller, whereupon Escrow Agent shall promptly
refund all Earnest Money to Purchaser, and Purchaser and Seller shall have no
further rights, obligations, or liabilities hereunder, except as may be
expressly provided to the contrary herein; or (ii) Purchaser shall have the
right to accept title to the Property subject to such defects and objections
with no reduction in the Purchase Price, in which event such defects and
objections shall be deemed "Permitted Exceptions"; or (iii) Purchaser may elect
to seek specific performance of this Agreement.

          16.  Condemnation. If, prior to the Closing, all or any part of the
               ------------
Property (which part allows the Tenant under the Leases to terminate the Leases
or otherwise reduce the rent payable thereunder) is subjected to a bona fide
threat of condemnation by a body having the power of eminent domain or is taken
by eminent domain or condemnation (or sale in lieu thereof), or if Seller has
received notice that any condemnation action or proceeding with respect to the
Property is contemplated by a body having the power of eminent domain, Seller
shall give Purchaser immediate written notice of such threatened or contemplated
condemnation or of such taking or sale, and Purchaser may by written notice to
Seller given within thirty (30) days of the receipt of such notice from Seller,
elect to cancel this Agreement. If Purchaser chooses to cancel this Agreement in
accordance with this Paragraph 16, then the Earnest Money shall be returned
immediately to Purchaser by Escrow Agent and the rights, duties, obligations,
and liabilities of the parties hereunder shall immediately terminate and be of
no further force and effect. If Purchaser does not elect to cancel this
Agreement in accordance herewith, this Agreement shall remain in full force and
effect and the sale of the Property contemplated by this Agreement, less any
interest taken by eminent domain or condemnation, or sale in lieu thereof, shall
be effected with no further adjustment and without reduction of the Purchase
Price, and at the Closing, Seller shall assign, transfer, and set over to
Purchaser all of the right, title, and interest of Seller in and to any awards
that have been or that may thereafter be made for such taking.

          17.  Damage or Destruction. If any of the Improvements shall be
               ---------------------
destroyed or damaged prior to the Closing, and the estimated cost of repair or
replacement exceeds One Hundred Thousand Dollars ($500,000.00) or if the Leases
shall terminate as a result of such damage, Purchaser may, by written notice
given to Seller within twenty (20) days after receipt of written notice from
Seller of such damage or destruction, elect to terminate this Agreement, in
which

                                      14
<PAGE>

event the Earnest Money shall immediately be returned by Escrow Agent to
Purchaser and except as expressly provided herein to the contrary, the rights,
duties, obligations, and liabilities of all parties hereunder shall immediately
terminate and be of no further force or effect. If Purchaser does not elect to
terminate this Agreement pursuant to this Paragraph 17, or has no right to
terminate this Agreement (because the damage or destruction does not exceed
$500,000.00 and the Leases remain in full force and effect), and the sale of the
Property is consummated, Purchaser shall be entitled to receive all insurance
proceeds paid or payable to Seller by reason of such destruction or damage under
the insurance required to be maintained by Seller pursuant to Paragraph 8(d)
hereof (less amounts of insurance theretofore received and applied by Seller to
restoration). If the amount of said casualty or rent loss insurance proceeds is
not settled by the date of Closing, Seller shall execute at Closing all proofs
of loss, assignments of claim, and other similar instruments to ensure that
Purchaser shall receive all of Seller's right, title, and interest in and under
said insurance proceeds.

          18.  Assignment.  Purchaser's rights and duties under this Agreement
               ----------
shall not be assignable except to an affiliate of Purchaser without the consent
of Seller which consent shall not be unreasonably withheld.

          20.  Broker's Commission. Seller has by separate agreement agreed to
               -------------------
pay a brokerage commission to The Stan Johnson Co. and First Fidelity Mortgage
Corporation, and TC Oklahoma City, Inc. (the "Brokers").  Purchaser and Seller
hereby represent each to the other that they have not discussed this Agreement
or the subject matter hereof with any real estate broker or agent other than
Brokers so as to create any legal right in any such broker or agent to claim a
real estate commission with respect to the conveyance of the Property
contemplated by this Agreement. Seller shall and does hereby indemnify and hold
harmless Purchaser from and against any claim, whether or not meritorious, for
any real estate sales commission, finder's fees, or like compensation in
connection with the sale contemplated hereby and arising out of any act or
agreement of Seller, including any claim asserted by Brokers and any broker or
agent claiming under Brokers.  Likewise, Purchaser shall and does hereby
indemnify and hold harmless Seller from and against any claim, whether or not
meritorious, for any real estate sales commission, finder's fees, or like
compensation in connection with the sale contemplated hereby and arising out of
any act or agreement of Purchaser, except any such claim asserted by Brokers and
any broker or agent claiming under Brokers.   This Paragraph 21 shall survive
the Closing or any termination of this Agreement.

          21.  Notices. Wherever any notice or other communication is required
               -------
or permitted hereunder, such notice or other communication shall be in writing
and shall be delivered by overnight courier, by hand, by telecopy (if
transmission is confirmed by the transmitting machine), or sent by U.S.
registered or certified mail, return receipt requested, postage prepaid, to the
addresses set out below or at such other addresses as are specified by written
notice delivered in accordance herewith:

          PURCHASER:     c/o Wells Capital, Inc.
                         6200 The Corners Parkway, Suite 250
                         Norcross, Georgia 30092
                         Attn: Mr. Michael C. Berndt
                         Telecopy No. (404) 200-8199

                                      15
<PAGE>

          with a copy to:    O'Callaghan & Stumm LLP
                             127 Peachtree Street, N. E., Suite 1330
                             Atlanta, Georgia 30303
                             Attn: William L. O'Callaghan, Esq.
                             Telecopy No. (404) 522-3080

          SELLER:            c/o OKC Real Estate Investments, Inc.
                             1601 N.W. Expressway, Suite 1200
                             Oklahoma City, Oklahoma 74118
                             Attn: Shaun Frankfurt
                             Telecopy No. (405) 858-4036

          with a copy to:    Hartzog, Conger & Cason
                             1600 Bank of Oklahoma Plaza
                             201 Robert S. Kerr
                             Oklahoma City, OK 73102
                             Attn: Joseph P. Hogsett, Esq.
                             Telecopy No. (405) 235-7329

          Any notice or other communication mailed as hereinabove provided shall
be deemed effectively given or received on the date of delivery, if delivered by
telecopy, hand or by overnight courier, or otherwise on the third (3rd) business
day following the postmark date of such notice or other communication.

          22.  Possession.  Possession of the Property shall be granted by
               ----------
Seller to Purchaser on the date of Closing, subject only to the Leases and the
Permitted Exceptions.

          23.  Time Periods. If the time period by which any right, option, or
               ------------
election provided under this Agreement must be exercised, or by which any act
required hereunder must be performed, or by which the Closing must be held,
expires on a Saturday, Sunday, or holiday, then such time period shall be
automatically extended through the close of business on the next regularly
scheduled business day.

          24.  Indemnities.  From and after a Closing hereunder, Seller hereby
               -----------
agrees to indemnify, defend and hold Purchaser free and harmless of and from any
and all claims of any kind or nature, arising out of the Seller's breach of its
representations, warranties, or covenants contained herein, or any personal
injury or property damage (other than damage to the Land, the building or the
building equipment) occurring in, on or about the Improvements before the
Closing Date, except to the extent any of the foregoing shall be expressly
assumed by Purchaser pursuant to the provisions hereof.  With respect to any
liabilities or obligations which, after the Closing Date, are the liabilities or
obligations of Purchaser under the provisions of this Agreement, or which have
been expressly assumed in writing by Purchaser, or which arise solely as a
result of the acts of Purchaser, Purchaser shall indemnify, defend, and hold
Seller, free and harmless from any and all claims in connection therewith.

                                      16

<PAGE>

          25.  Survival of Provisions. Except as otherwise expressly provided
               ----------------------
herein, all covenants, warranties, and agreements set forth in this Agreement
shall survive the Closing for a period of one year, and except for any claims
which are contained in a notice given to the other party prior to or at that
time, as of the first anniversary of Closing, the parties will be deemed to have
released one another from any and all claims, demands or liabilities associated
in any way with the Property or this Agreement.

          26.  Severability.  This Agreement is intended to be performed in
               ------------
accordance with, and only to the extent permitted by, all applicable laws,
ordinances, rules, and regulations. If any provision of this Agreement, or the
application thereof to any person or circumstance, shall, for any reason and to
any extent be invalid or unenforceable, the remainder of this Agreement and the
application of such provision to other persons or circumstances shall not be
affected thereby but rather shall be enforced to the greatest extent permitted
by law.

          27.  Authorization. Purchaser represents to Seller that this Agreement
               -------------
has been duly authorized and executed on behalf of Purchaser and constitutes the
valid and binding agreement of Purchaser, enforceable in accordance with its
terms, and all necessary action on the part of Purchaser to authorize the
transactions herein contemplated has been taken, and no further action is
necessary for such purpose.

          28.  General Provisions. No failure of either party to exercise any
               ------------------
power given hereunder or to insist upon strict compliance with any obligation
specified herein, and no custom or practice at variance with the terms hereof,
shall constitute a waiver of either party's right to demand exact compliance
with the terms hereof. This Agreement contains the entire agreement of the
parties hereto, and no representations, inducements, promises, or agreements,
oral or otherwise, between the parties not embodied herein shall be of any force
or effect. Any amendment to this Agreement shall not be binding upon the parties
hereto unless such amendment is in writing and executed by all parties hereto.
The provisions of this Agreement shall inure to the benefit of and be binding
upon the parties hereto and their respective heirs, legal representatives,
successors, and assigns. Time is of the essence of this Agreement. This
Agreement may be executed in multiple counterparts, each of which shall
constitute an original, but all of which taken together shall constitute one and
the same agreement. The headings inserted at the beginning of each paragraph are
for convenience only, and do not add to or subtract from the meaning of the
contents of each paragraph. This Agreement shall be construed and interpreted
under the laws of the State of Oklahoma.  Except as otherwise provided herein,
all rights, powers, and privileges conferred hereunder upon the parties shall be
cumulative but not restrictive to those given by law. All personal pronouns used
in this Agreement, whether used in the masculine, feminine, or neuter gender
shall include all genders, and all references herein to the singular shall
include the plural and vice versa. All references in this Agreement to "the
Seller's knowledge" or "the best of Seller's knowledge" shall refer to the
actual knowledge of Shaun Frankfurt and Ron Dixon, and shall not include implied
or imputed knowledge.

          29.  Effective Date. The "effective date" of this Agreement shall be
               --------------
deemed to be the date this Agreement is fully executed by both Purchaser and
Seller and a fully executed original counterpart of this Agreement has been
received by both Purchaser and Seller.

                                      17
<PAGE>

          30.  Duties as Escrow Agent.  In performing its duties hereunder,
               ----------------------
Escrow Agent shall not incur any liability to anyone for any damages, losses or
expenses, except for its gross negligence or willful misconduct, and it shall
accordingly not incur any such liability with respect to any action taken or
omitted in good faith upon advice of its counsel or in reliance upon any
instrument, including any written notice or instruction provided for in this
Agreement, not only as to its due execution and the validity and effectiveness
of its provision, but also as to the truth and accuracy of any information
contained therein that Escrow Agent shall in good faith believe to be genuine,
to have been signed or presented by a proper person and to conform to the
provisions of this Agreement.  Seller and Purchaser hereby agree to indemnify
and hold harmless Escrow Agent against any and all losses, claims, damages,
liabilities and expenses, including reasonable costs of investigation and legal
fees and disbursements, that may be imposed upon Escrow Agent or incurred by
Escrow Agent in connection with its acceptance or performance of its duties
hereunder as escrow agent, including without limitation, any litigation arising
out of this Agreement.  If any dispute shall arise between Seller and Purchaser
sufficient in the discretion of Escrow Agent to justify its doing so, Escrow
Agent shall be entitled to tender into the registry or custody of the clerk of
the Court for the county in which the Property is located or the clerk for the
United States District Court having jurisdiction over the county in which the
Property is located, any or all money (less any sums required to pay Escrow
Agent's attorneys' fees in filing such action), property or documents in its
hands relating to this Agreement, together with such pleadings as it shall deem
appropriate, and thereupon be discharged from all further duties under this
Agreement.  Seller and Purchaser shall bear all costs and expenses of any such
legal proceedings.

          IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed and their respective seals to be affixed hereunto as of the
day, month and year first above written.

          "SELLER":
          OKC REAL ESTATE INVESTMENTS, INC.

          By:  /s/ Shaun Frankfurt
               ------------------------------
               Shaun Frankfurt

          Its: President
               ------------------------------

          "PURCHASER":
          WELLS CAPITAL, INC.

          By:  /s/ Douglas P. Williams
               ------------------------------
               Douglas P. Williams

          Its: Senior Vice President
               ------------------------------

          "ESCROW AGENT":
          FIRST AMERICAN TITLE INSURANCE COMPANY

          By:  /s/ Betty J. Cummins
               ------------------------------
               Betty J. Cummins

          Its: Vice-President
               ------------------------------

                                      18
<PAGE>

                             Schedule of Exhibits
                             --------------------

          Exhibit "A"   -    Description of Land and Permitted Exceptions
          Exhibit "B"   -    Contracts
          Exhibit "C"   -    List of Due Diligence Materials
          Exhibit "D"   -    Form of Tenant Estoppel Certificate
          Exhibit "E"   -    Architect's Closing Certificate
          Exhibit "F"   -    Copy of Leases
          Exhibit "G"   -    List of Plans and Specifications
          Exhibit "H"   -    List of Insurance Policies
          Exhibit "I"   -    Bill of Sale Form
          Exhibit "J"   -    Blanket Transfer and Assignment Form
          Exhibit "K"   -    Assignment and Assumption of Leases Form<PAGE>

                                                                   EXHIBIT 10.15

                              FIRST AMENDMENT TO

                AGREEMENT FOR THE PURCHASE AND SALE OF PROPERTY

                      FOR THE AT&T CALL CENTER BUILDINGS
<PAGE>

               FIRST AMENDMENT TO REAL ESTATE PURCHASE CONTRACT
               ------------------------------------------------

     THIS FIRST AMENDMENT TO REAL ESTATE PURCHASE CONTRACT is executed by the
undersigned parties to that certain "Agreement for the Purchase and Sale of
Property" dated June 22, 2000 (the "Agreement"), providing for the purchase and
sale of certain real property located in Oklahoma County, Oklahoma (the
"Property").  The Agreement is amended in the following respects:

     1.   By agreement of the parties, the date of the Closing shall be December
28, 2000.  This First Amendment shall be effective as of the date of the Closing
(the "Effective Date").

     2.   Purchaser hereby assigns all of its rights and duties under the
Agreement to Wells Fund XII-REIT Joint Venture Partnership, a Georgia joint
venture partnership ("Assignee").  Assignee is an affiliate of Purchaser.

     3.   Seller hereby represents and warrants to Assignee that all
representations and warranties set forth in Section 7 of the Agreement are true
and correct as of the Effective Date.  In order to give Assignee additional
comfort relative to the representation and warranty contained in Section 7(t) of
the Agreement, Seller also agrees to use commercially reasonable efforts to
obtain and deliver to Assignee an estoppel certificate in substantially the form
attached hereto as Exhibit "A" as soon as reasonably possible after the
Effective Date.

     4.   As of the Effective Date, as evidenced by the acceptance letters
attached hereto as Exhibit "B", AT&T Corp. has accepted all of the Existing
Space (as defined in the Lease with AT&T Corp.)  and all of the Expansion Space
(as defined in the Lease with AT&T Corp.). Seller represents and warrants to
Assignee that AT&T Corp. is presently occupying all of the referenced space
except for certain portions of the Expansion Space located on the first floor of
the building (the "First Floor Space").  The Seller specifically agrees that,
notwithstanding the Closing, it will remain responsible for all of the following
matters (collectively, the "Post-Closing Obligations"):

          (a)  the delivery to Purchaser of an estoppel certificate executed by
     AT&T Corp. in substantially the form attached as Exhibit "D" to the
     Agreement;

          (b)  the exterior punchlist items described in Section 5 of the Tenant
     Estoppel Certificate executed by Jordan Associates, Inc.;

                                       1
<PAGE>

          (c)  the satisfaction of any requirements necessary to cause the
     temporary certificate of occupancy issued for the Expansion Space to become
     a permanent certificate of occupancy; and

          (d)  issuance by Smith-Roberts Associates, Inc. of a revision of its
     ALTA/CSM Land Title Survey, dated December 22, 2000, to delete therefrom
     the reference in the "Notes" to an "Unrecorded Easement", to reflect
     thereon the release of that portion of the water easement in favor of the
     City of Oklahoma City and that portion of the electricity easement in favor
     of Oklahoma Gas and Electric Company shown as running beneath a portion of
     the building.

     Seller shall resolve all of the referenced items at its expense as soon as
reasonably possible after the Effective Date.  If delays in the Seller's final
completion of the Post-Closing Obligations result in rental loss or other
damages to Assignee, Seller (and TCC pursuant to Section 5 below), will
indemnify and hold Assignee harmless with respect to any such damages.  Assignee
will cooperate with Seller as reasonably necessary to allow Seller to resolve
the referenced items and to recover from AT&T Corp. the rent for the Expansion
Space for the month of January 2001, any sums owed to Seller for rent and/or
operating cost reimbursements for the period prior to closing, and any sums owed
in connection with tenant improvement issues.

     5.   Seller agrees to cause Trammell Crow Company ("TCC") to issue a letter
of  guaranty, in the form attached hereto as Exhibit "C", whereby TCC will
guarantee the Seller's performance of the Post-Closing Obligations.

     6.   Seller agrees to instruct the Title Agent to withhold from its sales
proceeds and place in escrow the sum of $100,000 to further ensure the Seller's
performance of the Post-Closing Obligations.  At such time as Seller has
performed the Post-Closing Obligations, Purchaser will confirm the same in a
letter directed to the Title Agent, and the Title Agent will promptly release
all such funds to Seller; provided, however, in the event Seller fails to
perform the Post-Closing Obligations within 120 days after the Effective Date,
Assignee shall be entitled to receive an amount equal to $10,000.00 per month
from the referenced escrow for each month beyond such 120 day period that such
non-performance continues, until all Post-Closing Obligations are completed.

     7.   Seller agrees to instruct the Title Agent to pay to Assignee from
Seller's proceeds January rent attributable to the Expansion Space in the amount
of $78,500.00.  In the event Assignee receives a payment from AT&T Corp. for
some or all of the January rent attributable to the Expansion Space, Assignee
shall remit the same to Seller.

     Except as otherwise provided herein, all of the terms and provisions of the
Agreement shall remain in full force and effect.  Capitalized terms which are
not defined in this First Amendment shall have the meanings specified in the
Agreement.

                                       2
<PAGE>

     IN WITNESS WHEREOF, the parties have executed this First Amendment with the
intent that it be effective as of the Effective Date.

SELLER:                       OKC REAL ESTATE INVESTMENTS, INC., a Delaware
                              corporation

                                     /s/ Shaun Frankfurt
                              By:------------------------------------------
                                 Name:   Shaun Frankfurt
                                 Title:  President

PURCHASER:                    WELLS CAPITAL, INC.

                                     /s/ Douglas P. Williams
                              By:------------------------------------------
                                         Douglas P. Williams
                                 Name:-------------------------------------
                                 Title:  Executive V.P.
                                       ------------------------------------

                                       3
<PAGE>

APPROVED AND AGREED:
-------------------

WELLS FUND XII-REIT JOINT
VENTURE PARTNERSHIP, a Georgia joint venture partnership

By:  Wells Operating Partnership, L.P.,
     a Delaware limited partnership, as
     Administrative Venture Partner

By:  Wells Real Estate Investment
     Trust, Inc., a Maryland corporation,
     as General Partner

By: /s/ Douglas P. Williams
   --------------------------------------
   Name:  Douglas P. Williams
        ---------------------------------
   Title: Executive V.P
         --------------------------------

                                       4
<PAGE>

ACKNOWLEDGMENT BY ESCROW AGENT:
------------------------------

     The undersigned, as the Escrow Agent under the Agreement, agrees to comply
with the escrow provisions contained in the foregoing First Amendment to Real
Estate Purchase Contract, subject to the terms and conditions of Section 30 of
the Agreement.

                                              FIRST AMERICAN TITLE & TRUST
                                              COMPANY, Agent for First American
                                              Title Insurance Company

                                              By: /s/ Betty J. Cummins
                                                 -------------------------------
                                                 Name:  Betty J. Cummins
                                                 Title: Vice President

                                       5
<PAGE>

                                  EXHIBIT "A"
                                  -----------

                                   ESTOPPEL

Wells Fund XII-REIT Joint Venture Partnership
c/o Wells Management Company, Inc.
6200 The corners Parkway, Suite 250
Norcross, GA 30092

     Re:  Declaration of Protective Covenants, Quail Springs Office Park, dated
          April 27, 1983, and recorded in Book 4997, page 999, as amended by
          instruments recorded in Book 5230, page 44 and Book 7269, page 735
          (collectively, the "Declaration")

Ladies and Gentlemen:

     The undersigned is the Association under the Declaration and, understanding
that you have entered into a contract to purchase the real property and
improvements thereon (collectively, the "Property"), commonly known as 3201
Quail Springs Parkway, and further understanding that you  and any lender and/or
successor owner of the Property (collectively, "Owner"), will rely on the
information herein contained, hereby certifies to you as follows:

     1.   The Property is subject to the provisions of the Declaration and is
entitled to the rights, privileges and benefits thereunder.

     2.   The charges owed by the Owner (or any predecessor) to the Association
for the calendar year 2000 have been paid in full. The Annual Budget for the
Year 2001 is estimated to be $__________, is due and payable on or before
______________, 2001, and the portion thereof applicable to the Property is
$__________. There are no outstanding special assessments for capital
improvements and none are anticipated in the foreseeable future. There are no
other charges, expenses or other costs which are due and payable by Owner.

     3.   That to the best of the undersigned's knowledge, the Declaration is in
full force and effect, the Property, as improved, and the Owner are in full
compliance with the terms and conditions of the Declaration, including all plan
approval requirements, no event of default or default has occurred and is
continuing under the Declaration with respect to the Property and no event has
occurred which, with the passage of time or the giving of notice, or both, would
constitute an event of default or default.

     4.   The Association is a duly organized and validly formed nonprofit
corporation under the laws of the State of Oklahoma, is in good standing in the
State of Oklahoma, is not subject to any involuntary proceeding for dissolution
or liquidation thereof, and has obtained all requisite authorizations to execute
this Estoppel Certificate.
<PAGE>

     5.   The Declarant under the Declaration continues to be _________________.

     Agreed to this ______ day of December, 2000.

                                    Association:
                                    Quail Springs Office Park Owners'
                                    Association, Inc., an Oklahoma nonprofit
                                    corporation

                                    By:_________________________________________
                                       Name:____________________________________
                                       Title:___________________________________
<PAGE>

                                  EXHIBIT "B"
                                  -----------

          MEMORANDUM OF LEASE COMMENCEMENT AND ACCEPTANCE OF PREMISES
                         (First Floor Expansion Space)

     This Memorandum of Lease Commencement and Acceptance of Premises is made as
of December 7, 2000, by OKC Real Estate Investments, Inc. ("Landlord"), having
an office c/o TC Oklahoma City, Inc., 1601 N.W. Expressway, Suite 1200, Oklahoma
City, Oklahoma 73118, and AT&T Corp. ("Tenant"), having an office at 150 Mt.
Airy Road, Basking Ridge, New Jersey 07920. Landlord and Tenant agree to and
acknowledge the following matters:

     1.   Landlord and Tenant have entered into a Lease Agreement (the "Lease"),
covering certain lease premises commonly known as Suite 200, containing
approximately 103,500 rentable square feet (the "Existing Space" and "Expansion
Space" as defined in the Lease), in the property known as Quail Commerce Centre
located at 3201 Quail Springs Parkway as more particularly described in the
Lease (the "Premises"). Tenant took possession of and accepted (a) the Existing
Space on June 5, 2000, as set forth in the previous Memorandum of Lease
Commencement and Acceptance of Premises dated June 3, 2000 and (b) that portion
of the Expansion Space located on the second floor on December 10, 2000, as set
forth in the previous Memorandum of Lease Commencement and Acceptance of
Premises dated December 7, 2000.

     2.   Tenant has now also accepted possession of that portion of the
Expansion Space located on the first floor (the "First Floor Space") pursuant to
the Lease as suitable for the purpose for which they were leased. The Lease term
for the First Floor Space commences on December 28, 2000. The termination date
of the Lease term, excluding renewals and extensions, is November 30, 2010.

     3.   The beginning monthly rent presently payable under the Lease for the
First Floor Space is $39,250.00 with adjustments as described in the Lease.
Tenant is not entitled to rent concessions of any kind under the Lease for the
First Floor Space except as follows: None. No rent or other sum payable under
                                     ----
the Lease has been paid more than one month in advance.

     4.   Any improvements required by the terms of the Lease to be made by
Landlord for the First Floor Space have been completed to the satisfaction of
Tenant in all respects, and Landlord has fulfilled all of its duties for the
First Floor Space under the Lease.

     5.   The Lease is valid and in full force and effect, and, to the best of
Tenant's knowledge, neither Landlord nor Tenant is in default thereunder. Tenant
has no defense, setoff or counterclaim against Landlord arising out of the Lease
or in any way relating thereto, or arising out of any other transaction between
Tenant and Landlord, and no event has occurred and no condition exists, which
with the giving of notice or the passage of time, or both, will constitute a
default under the Lease.

     IN WITNESS WHEREOF, Landlord and Tenant has executed this Memorandum as of
December 7, 2000.

TENANT:                                      LANDLORD:

AT&T CORP.                                   OKC REAL ESTATE INVESTMENTS, INC.

By: /s/ Bill Blanton                         By: /s/ Shaun W. Frankfurt
    ---------------------------                  -----------------------------

Printed Name: Bill Blanton                   Printed Name: Shaun W. Frankfurt
              -----------------                            -------------------

Title: Southern Area Director                Title: President
       ------------------------                     --------------------------

                                  Page 1 of 3
<PAGE>

          MEMORANDUM OF LEASE COMMENCEMENT AND ACCEPTANCE OF PREMISES
                        (Second Floor Expansion Space)

     This Memorandum of Lease Commencement and Acceptance of Premises is made as
of Dec. 7, 2000, by OKC Real Estate Investments, Inc. ("Landlord"), having an
office c/o TC Oklahoma City, Inc., 1601 N.W. Expressway, Suite 1200, Oklahoma
City, Oklahoma 73118, and AT&T Corp. ("Tenant"), having an office at 150 Mt.
Airy Road, Basking Ridge, New Jersey 07920. Landlord and Tenant agree to and
acknowledge the following matters:

     1.   Landlord and Tenant have entered into a Lease Agreement (the "Lease"),
covering certain lease premises commonly known as Suite 200, containing
approximately 103,500 rentable square feet (the "Existing Space" and "Expansion
Space" as defined in the Lease), in the property known as Quail Commerce Centre
located at 3201 Quail Springs Parkway as more particularly described in the
Lease (the "Premises"). Tenant took possession of and accepted the Existing
Space on June 5, 2000, as set forth in the previous Memorandum of Lease
Commencement and Acceptance of Premises dated June 3, 2000.

     2.   Tenant has now also accepted possession of that portion of the
Expansion Space located on the second floor (the "Second Floor Space") pursuant
to the Lease as suitable for the purpose for which they were leased. The Lease
term for the Second Floor Space commences on December 10, 2000. The termination
date of the Lease term, excluding renewals and extensions, is November 30, 2010.

     3.   The beginning monthly rent presently payable under the Lease for the
Second Floor Space is $39,250.00 with adjustments as described in the Lease.
Tenant is not entitled to rent concessions of any kind under the Lease for the
Second Floor Space except as follows: None. No rent or other sum payable under
                                      ----
the Lease has been paid more than one month in advance.

     4.   Any improvements required by the terms of the Lease to be made by
Landlord for the Second Floor Space have been completed to the satisfaction of
Tenant in all respects, and Landlord has fulfilled all of its duties for the
Second Floor Space under the Lease.

     5.   The Lease is valid and in full force and effect, and, to the best of
Tenant's knowledge, neither Landlord nor Tenant is in default thereunder. Tenant
has no defense, setoff or counterclaim against Landlord arising out of the Lease
or in any way relating thereto, or arising out of any other transaction between
Tenant and Landlord, and no event has occurred and no condition exists, which
with the giving of notice or the passage of time, or both, will constitute a
default under the Lease.

     IN WITNESS WHEREOF, Landlord and Tenant has executed this Memorandum as of
Dec 7, 2000.

TENANT:                                 LANDLORD:

AT&T CORP.                              OKC REAL ESTATE INVESTMENTS, INC.

By: /s/ Bill Blanton                    By: /s/ Shaun W. Frankfurt
    -------------------------               -------------------------------

Printed Name: Bill Blanton              Printed Name: Shaun W. Frankfurt
              ---------------                         ---------------------

Title: Southern Area Director           Title: President
       ----------------------                  ----------------------------

                                  Page 2 of 3
<PAGE>

          MEMORANDUM OF LEASE COMMENCEMENT AND ACCEPTANCE OF PREMISES

          This Memorandum of Lease Commencement and Acceptance of Premises is
made as of June 3, 2000 by OKC Real Estate Investments, Inc. ("Landlord"),
having an office c/o TC Oklahoma City, Inc., 1601 N. W. Expressway, Suite 1200,
Oklahoma City, Oklahoma 73118, and AT&T Corp. ("Tenant"), having an office at
150 Mt. Airy Road, Basking Ridge, New Jersey 07920. Landlord and Tenant agree to
and acknowledge the following matters:

          1.   Landlord and Tenant have entered into a Lease Agreement (the
"Lease"), covering certain leased premises commonly know as Suite 200,
containing approximately 103,500 rentable square feet (the "Existing Space" and
"Expansion Space" as defined in the Lease), in the property know as Quail
Commerce Centre located at 3201 Quail Springs Parkway as more particularly
described in the Lease (the "Premises").

          2.   Tenant has accepted possession of the Existing Space pursuant to
the Lease as suitable for the purpose for which they were leased. The Lease term
for the Existing Space commences on June 5, 2000. The termination date of the
Lease term, excluding renewals and extensions, is November 30, 2010.

          3.   The beginning monthly rent presently payable under the Lease for
the Existing Space is $25,000.00 with adjustments as described in the Lease.
Tenant is not entitled to rent concessions of any kind under the Lease for the
Existing Space except as follows: None. No rent or other sum payable under the
                                  ----
Lease has been paid more than one month in advance.

          4.   Any improvements required by the terms of the Lease to be made by
Landlord for the Existing Space have been completed to the satisfaction of
Tenant in all respects, and Landlord has fulfilled all of its duties for the
Existing Space under the Lease.

          5.   The Lease is valid and in full force and effect, and, to the best
of Tenant's knowledge, neither Landlord nor Tenant is in default thereunder.
Tenant has no defense, setoff or counterclaim against Landlord arising out of
the Lease or in any way relating thereto, or arising out of any other
transaction between Tenant and Landlord, and no event has occurred and no
condition exists, which with the giving of notice or the passage of time, or
both, will constitute a default under the Lease.

     IN WITNESS WHEREOF, Landlord and Tenant has executed this Memorandum as of
June 3, 2000.

TENANT:                                LANDLORD:

AT&T CORP.                             OKC REAL ESTATE INVESTMENTS, INC.

By: /s/ Charles B. Alexander           By: /s/ Shaun W. Frankfurt
   ---------------------------------      ---------------------------------

Printed Name: Charles B. Alexander     Printed Name: Shaun W. Frankfurt
             -----------------------                -----------------------

Title:        Asset Manager            Title:        President
      ------------------------------         ------------------------------

                                  Page 3 of 3
<PAGE>

                                 EXHIBIT "C"
                                 -----------

                                 December __, 2000

Wells Fund XII-REIT Joint Venture Partnership
6200 The Corners Parkway, Suite 250
Norcross, GA 30092

     RE:  Agreement for the Purchase and Sale of Property dated June 22, 2000,
          as amended by the First Amendment to Real Estate Purchase Contract
          effective as of December 29, 2000 (Quail Commerce Centre, Oklahoma
          City, Oklahoma), together the "Contract"

Ladies and Gentlemen:

     This will confirm that Trammell Crow Company does hereby guarantee the
performance by OKC Real Estate Investments, Inc. ("OKC") of the "Post-Closing
Obligations", as  defined in the First Amendment to Real Estate Purchase
Contract described above.

     This Guaranty is an absolute and unconditional guaranty payment (if
necessary) and of performance.  The liability of Guarantor is co-extensive with
that of OKC and also joint and several and this Guaranty shall be enforceable
against the undersigned without the necessity of any suit or proceeding against
OKC and without the necessity of any notice of non-payment, non-performance or
non-observance or of any notice of acceptance of this Guaranty or of any other
notice or demand to which the undersigned might otherwise be entitled, all of
which we hereby expressly waive. The validity of this Guaranty and the
obligations hereunder shall in no way be terminated, affected, diminished or
impaired by reason of (a) the assertion or the failure to assert by you against
OKC of any of the rights or remedies otherwise available to you, or (b) any non-
liability of OKC under the Contract, whether by insolvency, discharge in
bankruptcy, or any other defect or defense which may now or hereafter exist in
favor of OKC.

               [add appropriate signature block for TCC officer]

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00020-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00020-of-00352.parquet"}]]