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                                                                    EXHIBIT 4.22


                                HINES II, INC.

                                FIRST AMENDMENT
                              TO CREDIT AGREEMENT



         This FIRST AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is dated as
of February 10, 1998 and entered into by and among HINES II, INC. ("Company"),
the financial institutions listed on the signature pages hereof ("Lenders") and
BT COMMERCIAL CORPORATION, as Agent for Lenders ("Agent"), and is made with
reference to that certain Credit Agreement dated as of December 16, 1997 (the
"Credit Agreement") among Company, Lenders and Agent. Capitalized terms used
herein without definition shall have the same meanings herein as set forth in
the Credit Agreement.


                                    RECITALS


         WHEREAS, Company has requested Lenders to amend the Credit Agreement to
extent the expiration date of the Canadian Lenders' Canadian Commitments; and

         WHEREAS, Company, Lenders and Agent desire to amend the Credit
Agreement to extend the expiration date of the Canadian Lenders' Canadian
Commitments;

         NOW, THEREFORE, in consideration of the premises and the agreements,
provisions and covenants herein contained, the parties hereto agree as follows:

         Section 1.  AMENDMENTS TO THE CREDIT AGREEMENT

         1.1  Amendments to Section 1:  Definitions

              Subsection 1.1 of the Credit Agreement is hereby amended by
    deleting the date "January 31, 1998" from the definition of Canadian Loan
    funding date contained therein and substituting the date "March 31, 1998"
    therefor.

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         1.2  Amendments to Section 2:  Amounts and Terms of Commitments and
              Loans

              Subsection 2.1A(ii) of the Credit Agreement is hereby amended by
    deleting the date "February 15, 1998" contained therein and substitution
    "March 31, 1998" therefor.

         Section 2.     CONDITIONS TO EFFECTIVENESS

         Section 1 of this Amendment shall become effective only upon the
satisfaction of all of the following conditions precedent (the date of
satisfaction of such conditions being referred to herein as the "First Amendment
Effective Date"):

         A.   On or before the First Amendment Effective Date, Company shall
deliver to Lenders (or to Agent for Lenders) executed copies of this Amendment.

         B.   Agent shall have received copies of this Amendment executed by
Requisite Lenders.

         C.   Company shall pay or cause to be paid to Agent for distribution to
each Canadian Lender the commitment fees required by subsection 2.3A(iii) of the
Credit Agreement.

         D.   On or before the First Amendment Effective Date, all corporate and
other proceedings taken or required to be taken in connection with the
transactions contemplated hereby and all documents incidental thereto not
previously found acceptable by Agent, acting on behalf of Lenders, and its
counsel shall be satisfactory in form and substance to Agent and such counsel,
and Agent and such counsel shall have received all such counterpart originals or
certified copies of such documents as Agent may reasonably request.

         Section 3.     REPRESENTATIONS AND WARRANTIES

         In order to induce Lenders to enter into this Amendment and to amend
the Credit Agreement in the manner provided herein, Company represents and
warrants to each Lender that the following statements are true, correct and
complete:

         A.   Corporate Power and Authority.  Company has all requisite
corporate power and authority to enter into this Amendment and to carry out the
transactions contemplated by, and perform its obligations under, the Credit
Agreement as amended by this Amendment (the "Amended Agreement").

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         B.   Authorization of Agreements.  The execution and delivery of this
Amendment and the performance of the Amended Agreement has been duly authorized
by all necessary corporate action on the part of Company.

         C.   Signature and Incumbency.  The signature and incumbency
certificates of officers of Company delivered in connection with the Amendment
correctly reflect, as of the First Amendment Effective Date, the signature and
incumbency of each officer of Company executing this Amendment.

         D.   No Conflict.  After giving effect to the amendment effected
hereby, the execution and delivery by Company of this Amendment and the
performance by Company do not and will not (i) violate any provision of any law
or any governmental rule or regulation applicable to Company or any of its
Subsidiaries, the Certificate or Articles of Incorporation or Bylaws of Company
or any of its Subsidiaries or any order, judgment or decree of any court or
other agency of government binding on Company or any of its Subsidiaries, (ii)
conflict with, result in a breach of or constitute (with due notice or lapse of
time or both) a default under any Contractual Obligation of Company or any of
its Subsidiaries, (iii) result in or require the creation or imposition of any
Lien upon any of the properties or assets of Company or any of its Subsidiaries
(other than Liens created under any of the Loan Documents in favor of Agent on
behalf of Lenders), or (iv) require any approval of stockholders or any approval
or consent of any Person under any Contractual Obligation of Company or any of
its Subsidiaries, except for such approvals or consents which have been obtained
on or before the First Amendment Effective Date and disclosed in writing to
Lenders.

         E.   Governmental Consents.  The execution and delivery by Company of
this Amendment and the performance by Company of the Amended Agreement do not
and will not require any registration with, consent or approval of, or notice
to, or other action to, with or by, any federal, state or other governmental
authority or regulatory body.

         F.   Binding Obligation.  This Amendment has been duly executed and
delivered by Company and this Amendment and the Amended Agreement are the
legally valid and binding obligations of Company, enforceable against Company in
accordance with their respective terms, except as may be limited by bankruptcy,
insolvency, reorganization, moratorium or similar laws relating to or limiting
creditors' rights generally or by equitable principles relating to
enforceability.

         G.   Incorporation of Representations and Warranties From Credit
Agreement.  After giving effect to the amendments effected hereby, the
representations and warranties contained in Section 5 of the Credit Agreement
are and will be true, correct and complete in all material respects on and as of
the First Amendment Effective Date to the same extent as though made on and as
of that date, except to the extent such representations and warranties
specifically relate to an earlier date, in which case they were true, correct
and complete in all material respects on and as of such earlier date.

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         H.   Absence of Default.  After giving effect to the amendments
effected hereby, no event has occurred and is continuing or will result from the
consummation of the transactions contemplated by this Amendment that would
constitute an Event of Default or a Potential Event of Default.


         Section 4.  MISCELLANEOUS

         A.   Reference to and Effect on the Credit Agreement and the Other Loan
Documents.

         (i) On and after the First Amendment Effective Date, each reference in
    the Credit Agreement to "this Agreement", "hereunder", "hereof", "herein" or
    words of like import referring to the Credit Agreement, and each reference
    in the other Loan Documents to the "Credit Agreement", "thereunder",
    "thereof" or words of like import referring to the Credit Agreement shall
    mean and be a reference to the Amended Agreement.

         (ii) Except as specifically amended by this Amendment, the Credit
    Agreement and the other Loan Documents shall remain in full force and effect
    and are hereby ratified and confirmed.

         (iii)  The execution, delivery and performance of this Amendment shall
    not, except as expressly provided herein, constitute a waiver of any
    provision of, or operate as a waiver of any right, power or remedy of Agent
    or any Lender under, the Credit Agreement or any of the other Loan
    Documents.

         B.   Fees and Expenses.  Company acknowledges that all costs, fees and
expenses as described in subsection 10.2 of the Credit Agreement incurred by
Agent and its counsel with respect to this Amendment and the documents and
transactions contemplated hereby shall be for the account of Company.

         C.   Headings.  Section and subsection headings in this Amendment are
included herein for convenience of reference only and shall not constitute a
part of this Amendment for any other purpose or be given any substantive effect.

         D.   Applicable Law.  THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF
THE PARTIES HEREUNDER SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED
IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK (INCLUDING
WITHOUT LIMITATION SECTION 5-1401 OF THE GENERAL OBLIGATIONS LAW OF THE STATE OF
NEW YORK), WITHOUT REGARD TO CONFLICTS OF LAWS PRINCIPLES.

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         E.   Counterparts; Effectiveness.  This Amendment may be executed in
any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed and delivered shall be deemed an
original, but all such counterparts together shall constitute but one and the
same instrument; signature pages may be detached from multiple separate
counterparts and attached to a single counterpart so that all signature pages
are physically attached to the same document.

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered by their respective officers thereunto duly
authorized as of the date first written above.



                                       HINES II, INC.



                                       By: /s/ Claudia Pieropan
                                           ------------------------------
                                       Title: CFO
                                              ---------------------------


                                       LENDERS:

                                       BT COMMERCIAL CORPORATION, as a Domestic
                                       Lender and as Agent



                                       By: signature illegible
                                           ------------------------------
                                       Title: Associate
                                              ---------------------------

                                       BT BANK OF CANADA,
                                       as a Canadian Lender



                                       By: /s/ James E. Kellar
                                           ------------------------------
                                       Title: Vice President
                                              ---------------------------


                                       By: /s/ Robert S. Vogtle
                                           ------------------------------
                                       Title: Vice President and Chief
                                              ---------------------------
                                       Financial Officer
                                       ----------------------------------

                                      S-1
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                                       BANKERS TRUST COMPANY,
                                       as an Issuing Lender

                                       By: signature illegible
                                           ------------------------------
                                       Title: Principal
                                              ---------------------------


                                       HARRIS TRUST AND SAVINGS BANK,
                                       as a Domestic Lender

                                       By: /s/ Karen Knuds
                                           ------------------------------
                                       Title: Vice President
                                              ---------------------------


                                       FLEET NATIONAL BANK,
                                       as a Domestic Lender



                                       By: signature illegible
                                           ------------------------------
                                       Title: Assistant Vice President
                                              ---------------------------


                                       LASALLE NATIONAL BANK,
                                       as a Domestic Lender



                                       By: signature illegible
                                           ------------------------------
                                       Title: First Vice President
                                              ---------------------------


                                       NATIONSBANK OF TEXAS, N.A.,
                                       as a Domestic Lender and Canadian Lender



                                       By: signature illegible
                                           ------------------------------
                                       Title: Vice President
                                              ---------------------------

                                      S-2
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                                       UNION BANK OF CALIFORNIA, N.A.,
                                       as a Domestic Lender and Canadian Lender



                                       By: /s/ Martin P. Valencia
                                           ------------------------------
                                       Title: Vice President
                                              ---------------------------


                                       BANK OF MONTREAL,
                                       as a Canadian Lender


                                       By: signature illegible
                                           ------------------------------
                                       Title:
                                             ----------------------------


                                       WELLS FARGO BANK, NATIONAL ASSOCIATION,
                                       as a Domestic Lender and Canadian Lender



                                       By: signature illegible
                                           ------------------------------
                                       Title: Vice President
                                              ---------------------------

                                      S-3