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                                                                   Exhibit 10.33

                          AGREEMENT AND PLAN OF MERGER
                                (PRIVATE MERGER)

      This Agreement and Plan of Merger (this "Agreement") is entered into as of
this 31st day of May 2001, by and between American Spectrum Realty, Inc., a
Maryland corporation (the "Company" or "American Spectrum") and Nooney Rider
Trail LLC (the "Merging Entity").

                                    RECITALS:

      WHEREAS, American Spectrum Operating Partnership, L.P. (the "Operating
Partnership"), or a subsidiary of American Spectrum or the Operating
Partnership, as the case may be, and the Merging Entity (the "Parties," and
individually, a "Party") hereto desire to merge the Merging Entity with and into
the Operating Partnership or a newly organized subsidiary of American Spectrum
or the Operating Partnership pursuant to the Delaware Revised Uniform Limited
Partnership Act (the "Delaware RULPA") and Missouri law, with the Operating
Partnership or such subsidiary, as the case may be, being the surviving entity
(the "Merger") as part of the consolidation transaction set forth in the
registration statement of the Company on Form S-4 including all amendments
thereto (the "Registration Statement"), filed with the Securities and Exchange
Commission (the "SEC") pursuant to the Securities Act of 1933, as amended (the
"Securities Act"), of which the Prospectus/Consent Solicitation Statement of the
Company (the "Prospectus/Consent Solicitation Statement") is a part; and

      WHEREAS, the Operating Partnership's limited partnership agreement permits
this Agreement and the consummation of the Merger; and

      WHEREAS, if a newly organized subsidiary of the Company or the Operating
Partnership is formed, its governing documents will permit this Agreement and
the consummation of the Merger, subject to approval of its Members; and

      WHEREAS, the Merging Entity has duly approved this Agreement and the
consummation of the Merger, subject to approval of its Members; and

      WHEREAS, the Parties hereto anticipate that the Merger will further
certain of their business objectives.

      NOW, THEREFORE, in consideration of the premises and the mutual promises
herein made, and in consideration of the representations, warranties, and
covenants herein contained, the receipt and sufficiency of which are
acknowledged, the Parties agree as follows:

                                    ARTICLE I
                                   DEFINITIONS

      As used in this Agreement, the following terms shall have the respective
meanings set forth below:
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      "Accredited Investor" has the meaning set forth in Section 10.2 below.

      "Affiliate" has the meaning set forth in Rule 12b-2 of the regulations
promulgated under the Securities Exchange Act of 1934, as amended.

      "Agreement" means this Agreement, as amended from time to time.

      "American Spectrum" has the meaning set forth in the preface above.

      "American Spectrum Certificate of Merger" has the meaning set forth in
Section 2.2 below.

      "American Spectrum Common Shares" shall mean the shares of common stock,
$.01 par value, of American Spectrum.

      "Articles of Incorporation" means the articles of incorporation of
American Spectrum.

      "Business Combination" has the meaning set forth in Section 5.1 below.

      "Bylaws" means the bylaws of American Spectrum.

      "Closing" has the meaning set forth in Section 2.3 below.

      "Closing Date" has the meaning set forth in Section 2.3 below.

      "Code" means the Internal Revenue Code of 1986, as amended.

      "Company" has the meaning set forth in the Preface above.

      "Delaware RULPA" has the meaning set forth in the first paragraph of the
Recitals above.

      "Effective Time" has the meaning set forth in Section 2.2 below.

      "Exchange Agent" has the meaning set forth in Section 5.3 below.

      "Limited Partnership Units" has the meaning set forth in Section 2.1
below.

      "Managing General Partner" means the managing general partner of the
Merging Entity where such Merging Entity is a limited partnership.

      "Managing Member" means the managing member of the Merging Entity where
such Merging Entity is a limited liability company.

      "Maryland GCL" has the meaning set forth in the first paragraph of the
Recitals above.


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      "Material Adverse Effect" means, as to any Party, a material adverse
effect on the business, properties, operations or condition (financial or
otherwise) which is not related to any industry-wide change in the economy or
market or other conditions affecting all businesses in the industry of the Party
to which the term is applied.

      "Member" means a member of the Merging Entity, where such Merging Entity
is a limited liability company.

      "Member Interests" has the meaning set forth in Section 2.1 below.

      "Merger" has the meaning set forth in the first paragraph of the Recitals
above.

      "Merging Entity" has the meaning set forth in the preface above.

      "Merging Entity's Certificate of Merger" has the meaning set forth in
Section 2.2 below.

      "Operating Partnership" has the meaning set forth in the Preface above.

      "Operating Partnership Unit Consideration" has the meaning set forth in
Section 5.1 below.

      "Operating Partnership Units" means limited partnership units of the
Operating Partnership.

      "Partner" means a partner of the Merging Entity, where such Merging Entity
is a limited partnership.

      "Party" or "Parties" has the meaning set forth in the preface above.

      "Person" means an individual, a partnership, a corporation, an
association, a joint stock company, a trust, a joint venture, a limited
liability company, an unincorporated organization, a governmental entity (or any
department, agency, or political subdivision thereof) or other entity.

      "Prospectus/Consent Solicitation Statement" has the meaning set forth in
the first paragraph of the Recitals above.

      "Registration Statement" has the meaning set forth in the first paragraph
of the Recitals above.

      "SEC" has the meaning set forth in the first paragraph of the Recitals
above.

      "Securities Act" has the meaning set forth in the first paragraph of the
Recitals above.

      "Share Consideration" has the meaning set forth in Section 5.1.


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      "Surviving Entity" has the meaning set forth in Section 2.1 below.

      "Tax" means any federal, state, local, or foreign income, gross receipts,
license, payroll, employment, excise, severance, stamp occupation, premium,
windfall profits, environmental (including taxes under Code (S) 59A), customs
duties, capital stock, franchise, profits, withholding, social security (or
similar), unemployment, disability, real property, personal property, sales,
use, transfer, registration, value added, alternative or add-on minimum,
estimated, or other tax of any kind whatsoever, including any interest, penalty,
or addition thereto, whether disputed or not.

                                   ARTICLE II
                         MERGER; EFFECTIVE TIME; CLOSING

2.1   Merger.

      Subject to the terms and conditions of this Agreement, the Delaware RULPA
and Missouri law, at the Effective Time, the Merging Entity and the Operating
Partnership or a subsidiary of American Spectrum or the Operating Partnership as
the case may be, (the "Surviving Entity") shall consummate the Merger in which
(i) the Merging Entity shall be merged with and into the Surviving Entity and
the separate existence of the Merging Entity shall cease to exist, (ii) the
Surviving Entity shall be the successor or surviving entity in the Merger and
shall continue to be governed by the laws of Delaware and (iii) the properties,
other assets and liabilities of the Merging Entity will be deemed to have been
transferred to the Surviving Entity. The Merger shall have the effects set forth
in the the Delaware RULPA and Missouri law. Pursuant to the Merger, the
Operating Partnership shall issue Operating Partnership Units in exchange for
the Members' units in the Merging Entity (the "Partnership Units").

2.2   Effective Time.

      On the Closing Date, subject to the terms and conditions of this
Agreement, the Merging Entity and American Spectrum shall (i) cause to be
executed (A) a certificate of merger in the form required by the Delaware RULPA
(the "Delaware Certificate of Merger"), and (B) a certificate of merger in the
form required by Missouri law (the "Merging Entity's Certificate of Merger"),
and (ii) cause the Delaware RULPA, and the Merging Entity's Certificate of
Merger to be filed with the Missouri Secretary of State. The Merger shall become
effective at (i) such time as the American Spectrum Certificate of Merger has
been duly filed with the Delaware Certificate of Merger is filed with the
Delaware Secretary of State, as the case may be or (ii) such other time as is
agreed upon by the Merging Entity and American Spectrum and specified in the
Merging Entity's Certificate of Merger and the Delaware Certificate of Merger.
Such time is hereinafter referred to as the "Effective Time."

      2.3   The Closing. The closing of the transactions contemplated by this
Agreement (the "Closing") shall take place at the offices of Proskauer Rose LLP,
1585 Broadway, New York, New York simultaneously with the Closing of the
Consolidation pursuant to the


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Prospectus/Consent Solicitation Statement (the "Closing Date"), but in no event
later than December 31, 2001, unless extended by the mutual agreement of the
Parties.


                                   ARTICLE III
                             [Intentionally omitted]


                                   ARTICLE IV
                      NAME; LIMITED PARTNERSHIP AGREEMENT;
                       GENERAL PARTNER OF SURVIVING ENTITY

A.    If the Surviving Entity is the Operating Partnership:

      4.1   Name.  The name of the surviving entity shall be American Spectrum
Operating Partnership, L.P.

      4.2   Limited Partnership Agreement. The limited partnership agreement of
the Operating Partnership, as in effect immediately prior to the Effective Time,
shall be the limited partnership agreement of the Surviving Entity until
thereafter amended as provided therein.

      4.3   General Partners. The general partners of the Operating Partnership
immediately prior to the Effective Time shall be the general partners of the
Surviving Entity from and after the Effective Time.

B.    If the Surviving Entity is a subsidiary of American Spectrum or the
Operating Partnership:

      4.1   Name.  The name of the surviving entity shall be the name of the
subsidiary.

      4.2   Limited Partnership Agreement. The limited partnership agreement or
constituent documents of the subsidiary, as in effect immediately prior to the
Effective Time, shall be the limited partnership agreement or the constituent
documents of the Surviving Entity until thereafter amended as provided therein.

      4.3   General Partners. The general partners or managing members of the
subsidiary immediately prior to the Effective Time shall be the general partners
or managing members of the Surviving Entity from and after the Effective Time.


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                                    ARTICLE V
                                  CONSIDERATION

      5.1   Operating Partnership Unit Consideration. (a) At the Closing, the
Members will be allocated Operating Partnership Units (the "Operating
Partnership Unit Consideration") in such amounts as shall be determined in
accordance with the final Prospectus/Consent Solicitation Statement. The Merging
Entity acknowledges that the amounts and terms may be different from that set
forth in the draft Prospectus/Consent Solicitation Statement.

      (b)   Prior to the Effective Time, if American Spectrum splits or combines
American Spectrum Common Shares; or pays a stock dividend or other stock
distribution in American Spectrum Common Shares, or in rights or securities
exchangeable or convertible into or exercisable for American Spectrum Common
Shares, or otherwise changes the American Spectrum Common Shares into, or
exchanges the American Spectrum Common Shares for, any other securities (whether
pursuant to or as part of a merger, consolidation, acquisition of property or
stock, separation, reorganization, or liquidation of American Spectrum as a
result of which American Spectrum stockholders receive cash, stock, or other
property in exchange for, or in connection with, their American Spectrum Common
Shares (a "Business Combination") or otherwise)), then the Operating Partnership
Units to be received by the Members of the Merging Entity will be appropriately
adjusted to reflect such event.

      (c)   At the Effective Time, by virtue of the Merger and without any
action by holders thereof, all of the Operating Partnership Units issued and
outstanding prior to the Effective Time shall remain issued and outstanding.

      5.2   Fractional American Spectrum Common Shares. No certificates
representing fractional Operating Partnership Units shall be issued. Each Member
who would otherwise be entitled to fractional Operating Partnership Units will
receive one Operating Partnership Unit for each fractional interest representing
50% or more of one Operating Partnership Unit. No Operating Partnership Unit
will be issued for a fractional interest representing less than 50% of an
Operating Partnership Unit.

      5.3   Issuance of Operating Partnership Units. American Spectrum shall
designate an exchange agent (the "Exchange Agent") to act as such in connection
with the issuance of certificates representing Operating Partnership Units
pursuant to this Agreement.

                                   ARTICLE VI
               REPRESENTATIONS AND WARRANTIES OF AMERICAN SPECTRUM
                          AND THE OPERATING PARTNERSHIP

      American Spectrum represents and warrants to the Members and the Merging
Entity that the statements contained in this Article VI are correct and complete
as of the date hereof:

      6.1   Organization, Qualification and Corporate Power.  American Spectrum
is a corporation duly organized, validly existing, and in good standing under
the laws of Maryland, as


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set forth in the Preface. American Spectrum is duly authorized to conduct
business and is in good standing under the laws of each jurisdiction where such
qualification is required, except where failure to so qualify or obtain
authorization would not have a Material Adverse Effect on American Spectrum. The
Operating Partnership is a limited partnership duly organized, validly existing
and in good standing under the laws of Delaware, as set forth in the Preface.
The Operating Partnership is duly authorized to conduct business and is in good
standing under the laws of each jurisdiction where such qualification is
required, except where failure to so qualify or obtain authorization would not
have a Material Adverse Effect on the Operating Partnership.

      6.2   Authorization for Common Stock. The Operating Partnership Units
will, when issued, be duly authorized, validly issued, fully paid and
nonassessable, and no stockholder or partner of American Spectrum will have any
preemptive right or similar rights of subscription or purchase in respect
thereof.

      6.3   Authorization of Transaction. American Spectrum and the Operating
Partnership have full power and authority (including full corporate and limited
partnership power and authority) to execute and deliver this Agreement and to
perform their obligations hereunder. The execution, delivery and performance by
American Spectrum and the Operating Partnership of this Agreement has been duly
and validly authorized by the board of directors of American Spectrum. This
Agreement constitutes the valid and legally binding obligation of American
Spectrum or the Operating Partnership, enforceable in accordance with its terms
and conditions. Neither American Spectrum nor the Operating Partnership is
required to give any notice to, make any filing with, or obtain any
authorization, consent, or approval of any government or governmental agency in
order to consummate the transactions contemplated by this Agreement, except in
connection with the federal securities laws, the Hart Scott Rodino Act, if
applicable, and any applicable "Blue Sky" or state securities laws.

      6.4   If a subsidiary of American Spectrum or the Operating Partnership is
the Merging Entity, the foregoing representations will apply to such subsidiary.

                                   ARTICLE VII
                    REPRESENTATIONS AND WARRANTIES CONCERNING
                               THE MERGING ENTITY

      The Merging Entity represents and warrants to American Spectrum and the
Operating Partnership that the statements contained in this Article VI are
correct and complete as of the date hereof.

      7.1   Organization, Qualification and Corporate Power. The Merging Entity
is a limited partnership/limited liability company duly organized, validly
existing, and in good standing under the laws of Missouri, as set forth in the
Preface. The Merging Entity is duly authorized to conduct business and is in
good standing under the laws of each jurisdiction where such qualification is
required, except where failure to so qualify or obtain authorization would not
have a Material Adverse Effect on the Merging Entity.


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      7.2   Authorization of Transaction. The Merging Entity has full power and
authority to execute and deliver this Agreement and to perform its obligations
hereunder. Subject to approval of the Merger by the Merging Entity's Members,
this Agreement constitutes the valid and legally binding obligation of the
Merging Entity, enforceable in accordance with its terms and conditions. The
Merging Entity is not required to give any notice to, make any filing with, or
obtain any authorization, consent or approval of any governmental agency in
order to consummate the transactions contemplated by this Agreement, except in
connection with federal securities laws, the Hart Scott Rodino Act, if
applicable, and any applicable "Blue Sky" or state securities laws.

      7.3   Merging Entity Acknowledgment

            The Merging Entity acknowledges that

                  (A)   the Operating Partnership Units to be issued at the
Closing have not been registered under the Securities Act of 1933 or state
securities laws by reason of a specific exemption or exemptions from
registration under the Securities Act of 1933 and applicable state securities
laws and, if such Operating Partnership Units are represented by certificate,
such certificates will bear a legend to such effect,

                  (B)   the Operating Partnership's reliance on such exemptions
is predicated in part on the accuracy and completeness of the representations
and warranties contained herein,

                  (C)   the Operating Partnership Units to be issued at the
Closing may not be resold or otherwise distributed unless registered under the
Securities Act of 1933 and applicable state securities laws, or unless an
exemption from registration is available,

                  (D)   there is no public market for such Operating Partnership
Units or for the American Spectrum Common Shares, and

                  (E)   The Operating Partnership has no obligations or
intention to register such American Spectrum Common Shares or Operating
Partnership Units under the Securities Act of 1933 or any state securities laws
or to take any action that would make available any exemption from the
registration requirements of such laws, except as provided in the Registration
Rights Agreement (referred to below).

            (i)   The Merging Entity hereby acknowledges that because of the
restrictions on the transfer or assignment, each Member may have to bear the
economic risk of the investment commitment evidenced by this Agreement and any
of the Operating Partnership Units issued hereunder for an indefinite period of
time, although, if applicable,

                  (A)   under the terms of the Exchange Rights Agreement,
Operating Partnership Units will, subject to the limitations set forth in the
Exchange Rights Agreement, be exchangeable at the request of the holder thereof
at any time after the first anniversary of their


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issuance for cash based on their fair market value or, at the option of American
Spectrum, for American Spectrum Common Shares, and

                  (B)   the holder of any such American Spectrum Common Shares
issued upon exchange of Units will be afforded certain rights to have such
American Spectrum Common Shares registered under the Securities Act of 1933 and
applicable state securities laws pursuant to the Registration Rights Agreement.

                                  ARTICLE VIII
                              PRE-CLOSING COVENANTS

      The Parties agree as follows with respect to the period between the
execution of this Agreement and the Closing:

      8.1   General. Each of the Parties will use its reasonable best efforts to
take all action and to do all things necessary, proper or advisable in order to
consummate and make effective the transactions contemplated by this Agreement
(including satisfaction, but not waiver, of the closing conditions set forth in
Article IX below).

      8.2   Notices and Consents. Each of the Parties shall give any notices to,
make any filings with, and use its reasonable best efforts to obtain any
authorizations, consents, and approvals of governments and governmental agencies
in connection with the matters referred to in Sections 10.1 below.

      8.3   Execution of Instruments. The Merging Entity shall cause each of its
Members or Members to execute the Instruments set forth in Section 10.1(g) to
(i) and 10.3 (if applicable) below.

      8.4   American Spectrum shall execute the documents to be executed by it
pursuant to Section 10.1(g) and (h) below.


                                   ARTICLE IX
                             POST-CLOSING COVENANTS

      The Parties agree as follows with respect to the period following the
Closing:

      9.1   General. In the event that at any time after the Closing any further
action is necessary or desirable to carry out the purposes of this Agreement,
each of the Parties will take such further action (including the execution and
delivery of such further instruments and documents) as any other Party
reasonably may request, all at the sole cost and expense of the requesting
Party. The Merging Entity acknowledge and agree that from and after the Closing,
the Surviving Entity will be entitled to possession of all documents, books,
records (including Tax records), agreements and financial data of any sort
relating to the Merging Entity but will provide


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the Partners or Members with reasonable access to such documents, books and
records upon request.

      9.2   Litigation Support. In the event and for so long as any Party
actively is contesting or defending against any action, suit, proceeding,
hearing, investigation, charge, complaint, claim, or demand in connection with
(i) any transaction contemplated under this Agreement or (ii) any fact,
situation, circumstance, status, condition, activity, practice, plan,
occurrence, event, incident, action, failure to act, or transaction on or prior
to the Closing Date involving the Merging Entity, the other Party will cooperate
with him and his counsel in the contest or defense, make available their
personnel, and provide such testimony and access to their books and records as
shall be necessary in connection with the contest or defense, all at the sole
cost and expense of the contesting or defending Party.

      9.3   Share Registration.  American Spectrum shall use commercially
reasonable efforts to register the American Spectrum Common Shares promptly
following the first anniversary of the consummation of the Merger.

      9.4   (a) The Surviving Entity shall not engage in a "Gain Event" (as
defined below), during the Restricted Period, (as defined below), provided that
(i) the Surviving Entity may engage in an exchange or other disposition or
transaction which does not cause the Members who hold Operating Partnership
Units to recognize gain or federal income tax purposes (including, without
limitation, a transaction pursuant to Section 1031 of the Code or any successor
provision which would not cause such recognition of gain), and (ii) the
Surviving Entity may engage in a Gain Transaction, provided that, as a condition
precedent or concurrent, the Surviving Entity or its affiliates pays to the
Members or any successor holder of Operating Partnership Units an amount equal
to the sum of (A) any federal, state and local taxes resulting from the
recognition of gain based upon the assumption that the maximum rate applicable
to income or gains under federal, state and local income tax laws is applicable
and (B) an additional payment in an amount equal to the amount such that, after
payment by each Member (or successor) of all taxes (including interest and
penalties) on amounts received under clause (A) and this clause (B), the Member
(or successor) retains an amount equal to the amount described in clause (A).

            (b) The restriction imposed by Section 9.4(a) shall lapse at such
time as the number of Operating Partnership Units which have not been converted
to American Spectrum Common Shares is less than 50% of the Operation Partnership
Units Issued pursuant to this agreement.

            (c) Nothing contained in this Section shall be construed to limit
the rights of any lender or other secured party to foreclose on, or otherwise
dispose of, the Property and in such event, no payments shall be due to the
Members or their successors.

            (D) "Gain Event" means, if such event occurs prior to October 31,
2007 (the "Restricted Period"), the sale or other taxable disposition of all or
any portion of the real property (the "Property") owned by the Merging Entity or
the repayment, refinancing or modification of


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any mortgage loan secured by the Property other than as a result of a regularly
scheduled repayment of the mortgage loan in accordance with its terms, as in
effect at the date hereof.

                                    ARTICLE X
                        CONDITIONS TO OBLIGATION TO CLOSE

      10.1  Conditions to Each Party's Obligation. The respective obligations of
American Spectrum or the Operating Partnership, the Partners or Members and the
Merging Entity to consummate the transactions contemplated by this Agreement are
subject to the fulfillment at or prior to the Closing Date of each of the
following conditions, which conditions may be waived upon the written consent of
American Spectrum or the Operating Membership and the Partners or Members:

      (a)   Consents. The parties shall have obtained all consents of third
parties required in connection with the consummation of the transaction
contemplated hereby.

      (b)   Governmental Approvals. The Parties shall have received all other
authorizations, consents, and approvals of governments and governmental agencies
required in connection with the consummation of the transaction contemplated
hereby.

      (c)   No Injunction or Proceedings. There shall not be an unfavorable
injunction, judgment, order, decree, ruling, or charge would, in the reasonable
judgment of American Spectrum, prevent consummation of any of the transactions
contemplated by this Agreement.

      (d)   No Suspension of Trading, Etc. At the Effective Time, there shall be
no declaration of a banking moratorium by federal or state authorities or any
suspension of payments by banks in the United States (whether mandatory or not)
or of the extension of credit by lending institutions in the United States, or
commencement of war or other international, armed hostility or national calamity
directly or indirectly involving the United States, which war, hostility or
calamity (or any material acceleration or worsening thereof), in the sole
judgment of American Spectrum, would have a Material Adverse Effect on the
Merging Entity or, in the sole judgment of the Partners or Members, would have a
Material Adverse Effect on American Spectrum.

      (e)   The Consolidation pursuant to the Prospectus/Consent Solicitation
Statement shall have closed or be closing simultaneously with the Closing.

      (f)   American Spectrum Common Shares shall have been approved for listing
on notice of issuance on a national securities exchange acceptable to American
Spectrum.

      (g)   Registration Rights Agreement. A registration rights agreement or
customary terms, pursuant to which American Spectrum agrees to use commercially
reasonable efforts to register the American Spectrum Common Shares issued or
issuable in exchange for Operating Partnership Units shall have been executed
and delivered hereto.


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      (h)   Exchange Rights Agreement. An exchange rights agreement on customary
terms shall have been entered into by the parties hereto, which shall permit
exchange of the Operating Partnership Units for American Spectrum Common Shares
subject to customary limitations on and after the first anniversary of the
Closing, shall have been executed and delivered.

      (i)   The Merger shall have been approved by the required vote of the
Members of the Merging Entity.

      10.2  Conditions to Obligation of the Merging Entity. The obligations of
the Merging Entity to consummate the transactions contemplated hereby and take
the actions to be performed by it in connection with the Closing are subject to
satisfaction of the following additional conditions:

      The Operating Partnership shall have delivered to the Members Limited
Partnership Unit Consideration pursuant to Section 5.1, merged to Section 10.3.

      10.3  Conditions to Obligation of the Operating Partnership. The
obligations of the Operating Partnership to consummate the transactions
contemplated hereby and take the actions to be performed by it in connection
with the Closing are subject to satisfaction of the following additional
condition:

      The obligation of the Operating Partnership to deliver Operating
Partnership Units to any Members of the Merging Activity shall be subject to
such Member of the Merging Entity shall have executed the signature page of the
Agreement of Limited Partnership of the Operating Partnership and such other
documents as shall be necessary for admission as a limited partner of the
Operating Partnership.

                                   ARTICLE XI
                                   TERMINATION

      11.1  Termination by Mutual Consent. This Agreement may be terminated and
the Merger may be abandoned at any time prior to its Effective Time, before or
after the approval of the Partners or Members of the Merging Entity or American
Spectrum or the Operating Partnership, respectively, either by the mutual
written consent of American Spectrum or the Operating Partnership and the
Merging Entity or by the mutual action of the board of directors of American
Spectrum or the general partner of the Operating Partnership, and the Managing
General Partner or Managing Member of the Merging Entity.

      11.2  Termination by Either American Spectrum or the Operating Partnership
or by the Merging Entity. This Agreement may be terminated and the Merger may be
abandoned (a) by action of American Spectrum or the Operating Partnership in the
event of a failure of a condition to the obligations of American Spectrum and
the Operating Partnership set forth in Section 9.1 of this Agreement; (b) by the
Managing Member or the vote of a majority in interest of the Members or Members
of the Merging Entity in the event of a failure of a condition to the
obligations of the Merging Entity set forth in Section 9.1 or 9.2 of this
Agreement; or (c) if a


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United States or federal or state court of competent jurisdiction or United
States federal or state governmental agency shall have issued an order, decree
or ruling or taken any other action permanently restraining, enjoining or
otherwise prohibiting the transactions contemplated by this Agreement and such
order, decree, ruling or other action shall have become final and non-
appealable; provided, in the case of a termination pursuant to clause (a) or (b)
above, that the terminating party shall not have breached in any material
respect its obligations under this Agreement in any manner that shall have
proximately contributed to the occurrence of the failure referred to in said
clause.

      11.3  Effect of Termination and Abandonment. In the event of termination
of this Agreement and abandonment of the Merger pursuant to this Article XI, no
Party hereto (or any of its directors, officers, Managing General Partners,
Managing Members, Limited Partners or Members) shall have any liability or
further obligation to any other Party to this Agreement, except that nothing
herein will relieve any Party from liability for any breach of this Agreement.


                                   ARTICLE XII
                                  MISCELLANEOUS

      12.1  No Third-Party Beneficiaries. This Agreement shall not confer any
rights or remedies upon any Person other than the Parties and their respective
successors and permitted assigns.

      12.2  Entire Agreement. This Agreement (including the documents referred
to herein) constitutes the entire agreement among the Parties and supersedes any
prior understandings, agreements, or representations by or among the Parties,
written or oral, to the extent they related in any way to the subject matter
hereof.

      12.3  Succession and Assignment. This Agreement shall be binding upon and
inure to the benefit of the Parties named herein and their respective successors
and permitted assigns. No Party may assign either this Agreement or any of its
rights, interests, or obligations hereunder without the prior written approval
of American Spectrum or the Operating Partnership and the Partners or Members;
provided, however, that American Spectrum or the Operating Partnership may (i)
assign any or all of its rights and interests hereunder to one or more of its
Affiliates and (ii) designate one or more of its Affiliates to perform its
obligations hereunder (in any or all of which cases American Spectrum or the
Operating Partnership nonetheless shall remain responsible for the performance
of all of its obligations hereunder).

      12.4  Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original but all of which
together will constitute one and the same instrument.

      12.5  Headings. The section headings contained in this Agreement are
inserted for convenience only and shall not affect in any way the meaning or
interpretation of this Agreement.


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<PAGE>   14
      12.6  Notices. All notices, requests, demands, claim, or other
communication hereunder shall be deemed duly given, as of the date two business
days after mailing, if it is sent by registered or certified mail, return
receipt requested, postage prepaid, and addressed to the intended recipient as
set forth below:

      If to the Merging Entity:

      c/o William J. Carden
      Chief Executive Officer
      American Spectrum Realty, Inc.
      1800 East Deere Avenue
      Santa Ana, California  92705



      With copy to:

      Proskauer Rose LLP
      1585 Broadway
      New York, NY  10036
      Attn:  Peter M. Fass, Esq.
      Telecopy:  (212) 969-2900

      If to American Spectrum:

      William J. Carden
      Chief Executive Officer
      American Spectrum Realty, Inc.
      1800 East Deere Avenue
      Santa Ana, California  92705

      With copy to:

      Proskauer Rose LLP
      1585 Broadway
      New York, NY  10036
      Attn:  Peter M. Fass, Esq.
      Telecopy:  (212) 969-2900

      If to the Operating Partnership:

      American Spectrum Operating Partnership, L.P.
      c/o  William J. Carden
      Chief Executive Officer
      American Spectrum Realty, Inc.


                                       14
<PAGE>   15
      1800 East Deere Avenue
      Santa Ana, California  92705

      With copy to:

      Proskauer Rose LLP
      1585 Broadway
      New York, NY  10036
      Attn:  Peter M. Fass, Esq.
      Telecopy:  (212) 969-2900


Any Party may send any notice, request, demand, claim or other communication
hereunder to the intended recipient at the address set forth above using any
other means (including personal delivery, expedited courier, messenger service,
telecopy, telex, ordinary mail, or electronic mail), but no such notice,
request, demand, claim, or other communication shall be deemed to have been duly
given unless and until it actually is received by the intended recipient. Any
Party may change the address to which notices, requests, demands, claims, and
other communications hereunder are to be delivered by giving the other Party
notice in the manner herein set forth.

      12.7  Governing Law. This Agreement shall be governed and construed in
accordance with the laws of the State of Maryland without giving effect to any
choice or conflict of law provision or rules (whether of the State of Maryland
or any other jurisdiction) that would cause the application of the laws of any
jurisdiction other than the State of Maryland.

      12.8  Amendments and Waivers. No amendment of any provision of this
Agreement shall be valid unless the same shall be in writing and signed by
American Spectrum and the Merging Entity. No waiver by any party of any default,
misrepresentation, or breach of warranty or covenant hereunder, whether
intentional or not, shall be deemed to extend to any prior or subsequent
default, misrepresentation, or breach of warranty or covenant hereunder or
affect in any way any rights arising by virtue of any prior or subsequent such
occurrence.

      12.9  Severability. Any term or provision of this Agreement that is
invalid or unenforceable in any situation in any jurisdiction shall not affect
the validity or enforceability of the remaining terms and provisions hereof or
the validity or enforceability of the offending term or provision in any other
situation or in any other jurisdiction.

      12.10 Expenses. Each of the Parties will bear its own costs and expenses
(including legal fees and expenses) incurred in connection with this Agreement
and the transactions contemplated hereby, except to the extent set forth in the
Prospectus/Consent Solicitation Statement.

      12.11 Construction. The Parties have participated jointly in the
negotiation and drafting of this Agreement. In the event an ambiguity or
question of intent or interpretation arises, this Agreement shall be construed
as if drafted jointly by the Parties and no presumption or burden of


                                       15
<PAGE>   16
proof shall arise favoring or disfavoring any Party by virtue of the authorship
of any of the provisions of this Agreement. Any reference to any federal, state,
local or foreign statute or law shall be deemed also to refer to all rules and
regulations promulgated thereunder, unless the context requires otherwise. The
word "including" shall mean including without limitation. The Parties intend
that each representation, warrant, and covenant contained herein in any respect,
the fact that there exists another representation, warranty, or covenant
contained herein in any respect, the fact that there exists another
representation, warranty, or covenant relating to the same subject matter
(regardless of the relative levels of specificity) which the Party has not
breached shall not detract from or mitigate the fact that the Party is in breach
of the first representation, warranty or covenant.

      12.12 Specific Performance. Each of the Parties acknowledges that the
other Party would be damaged irreparably in the event any of the provisions of
this Agreement are not performed in accordance with their specific terms or
otherwise are breached. Accordingly, each of the Parties agrees that the other
Party shall be entitled to an injunction or injunctions to prevent breaches of
the provisions of this Agreement and to enforce specifically this Agreement and
the terms and provisions hereof in any action instituted in any court of the
United States or any state thereof having jurisdiction over the Parties and the
matter (subject to the provisions set forth in Section 12.13 below), in addition
to any other remedy to which they may be entitled, at law or in equity.

      12.13 Submission to Jurisdiction. Each of the Parties submits to the
jurisdiction of any state or federal court sitting in the State of California,
in any action or proceeding arising out of or relating to this Agreement and
agrees that all claims in respect of the action or proceeding may be heard and
determined in any such court.

      12.14 Impracticability of Merger. The Merging Entity agrees that if for
any reason it is impracticable to merge the Merging Entity with or into American
Spectrum or the Operating Partnership, as the case may be, but the conditions
are otherwise satisfied, that it will transfer all of its assets to American
Spectrum or the Operating Partnership. American Spectrum agrees that, in such
case, American Spectrum or the Operating Partnership shall assume all of the
liabilities of the Merging Entities. The terms of such transfer will be
substantially on the terms set forth herein.

      12.15 Further Assurances; Further Actions. Each of the parties shall,
without further consideration, take such action and execute and deliver such
documents as may be necessary to carry out this agreement.

                  REMAINDER OF PAGE INTENTIONALLY LEFT BLANK


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<PAGE>   17
      IN WITNESS WHEREOF, the Parties have executed this Agreement as of the
date first above written.

                        AMERICAN SPECTRUM REALTY, INC.

                        By:   /s/ William J. Carden
                              --------------------------------------------------
                              Name
                              Title


                        NOONEY RIDER TRAIL LLC

                        By: S-P Properties, Inc.
                        By:   /s/ William j. Carden
                              --------------------------------------------------
                              Name
                              Title  General Partner


                        AMERICAN SPECTRUM REALTY OPERATING
                        PARTNERSHIP L.P.

                        By:  AMERICAN SPECTRUM REALTY, INC.


                        By:   /s/ William J. Carden
                              --------------------------------------------------
                              Name
                              Title


                                       17