<PAGE>   1
                                                                   EXHIBIT 10.13



                               AMENDMENT NO. 3 TO
                  MASTER CONSTRUCTION LINE OF CREDIT AGREEMENT

         THIS AMENDMENT NO. 3 TO MASTER CONSTRUCTION LINE OF CREDIT AGREEMENT,
dated as of March 1, 2000 ("THIS AMENDMENT"), among the following:

                  (i) ALTERRA HEALTHCARE CORPORATION, a Delaware corporation
         formerly known as Alternative Living Services, Inc. (herein, together
         with its successors and assigns, the "COMPANY");

                  (ii) ALS NATIONAL, INC., a Delaware corporation (a
         "BORROWER");

                  (iii) the lending institutions listed on the signature pages
         hereof (the "LENDERS");

                  (iv) BANK OF AMERICA, NATIONAL ASSOCIATION, as successor to
         Bank of America National Trust and Savings Association, a national
         banking association, and SOUTHTRUST BANK, NATIONAL ASSOCIATION, a
         national banking association, as Co-Agents; and

                  (v) KEY CORPORATE CAPITAL INC., a Michigan corporation, as
         administrative agent (the "ADMINISTRATIVE AGENT").

         PRELIMINARY STATEMENTS:

         (1) The parties hereto entered into the Master Construction Line of
Credit Agreement, dated as of October 6, 1998, as amended by Amendment No. 1
thereto, dated as of January 5, 1999, and Amendment No. 2 thereto, dated as of
May 5, 1999 (as so amended, the "CREDIT AGREEMENT"; with the terms defined
therein, or the definitions of which are incorporated therein, being used herein
as so defined).

         (2) The parties hereto desire to change certain of the terms and
provisions of the Credit Agreement, all as more fully set forth below.

         NOW, THEREFORE, the parties hereby agree as follows:

         SECTION 1. AMENDMENTS, ETC.

         1.1. INTEREST. Effective on the Effective Date of this Amendment
provided for in section 4 hereof, section 2.9 (b) of the Credit Agreement is
amended to read in its entirety as follows:

                  (b) The unpaid principal amount of each Loan which is a
         Eurodollar Loan shall bear interest from the date of the Borrowing
         thereof until maturity (whether by acceleration or otherwise) at a rate
         per annum which shall at all times be the relevant Eurodollar Rate for
         such Loan PLUS (i) 200 basis points per annum, at all times during the
         period from the date of this Agreement through December 31, 1999, or
         (ii) 260 basis points per annum, at all times thereafter; PROVIDED that
         if (A) the New Capital Commitment Requirement is satisfied by April 20,
         2000, (B) the New Capital Funding Requirement is satisfied by June 30,
         2000, and (C) the Administrative Agent notifies the parties hereto




<PAGE>   2

         that such conditions have been satisfied (which the Administrative
         Agent shall issue promptly upon satisfaction of such conditions), then
         on the effective date of such notice from the Administrative Agent, but
         not earlier than July 1, 2000, the interest rate margin specified in
         clause (ii) above shall change from 260 basis points to 237.50 basis
         points.

         1.2. REDUCTION IN TOTAL TRANCHE A COMMITMENT. Effective on the
Effective Date of this Amendment provided for in section 4 hereof, the Total
Tranche A Commitment shall be partially and permanently reduced to $75,000,000
in accordance with section 4.1(d) of the Credit Agreement and the Administrative
Agent and the Lenders party hereto waive any requirement for prior notice of
such reduction under section 4.1 or any other applicable provision of the Credit
Agreement. After giving effect to the foregoing, Annex I to the Credit Agreement
is amended to reflect the following Tranche A Commitments:
<TABLE>
<CAPTION>
                                                                            TRANCHE A
  NAME OF LENDER                                                           COMMITMENT

<S>                                                                       <C>
  Key Corporate Capital Inc.                                              $17,500,000

  Bank of America National Trust and Savings Association                  $10,000,000

  SouthTrust Bank, National Association                                   $10,000,000

  Fleet National Bank                                                      $9,375,000

  Bank One, Texas, N.A.                                                    $9,375,000

  Comerica Bank                                                            $9,375,000

  U.S. Bank                                                                $9,375,000

           TOTAL                                                          $75,000,000
</TABLE>

         1.3. ADDITIONAL SUPPLEMENTAL RESERVE; MODIFICATION OF SUPPLEMENTAL
RESERVE COLLATERAL Arrangements. (a) Effective on the Effective Date of this
Amendment provided for in section 4 hereof, section 6.2 (g) of the Credit
Agreement is amended by adding the following at the end thereof:

         In addition to the foregoing, for each Project in which such Project's
         Closing Date is on or after January 1, 2000, cash and/or Cash
         Equivalents in an amount at least equal to an additional five percent
         (5%) of all costs and expenses of the acquisition and construction of
         such Project (including soft costs) and anticipated operating deficits
         through a full 12 months of full operation, as reflected in the Project
         Summary & Feasibility Report for such Project, (the "ADDITIONAL
         SUPPLEMENTAL RESERVE"), shall have been pledged and deposited by the
         Company with the Collateral Agent under the Supplemental Reserve Pledge
         Agreement.


         (b) The Lenders hereby consent to the execution and delivery of
Amendment No. 1 to Supplemental Reserve Pledge Agreement, substantially in the
form attached as Exhibit A hereto ("AMENDMENT NO. 1 TO SUPPLEMENTAL RESERVE
PLEDGE AGREEMENT").

                                       2
<PAGE>   3

         1.4. FINANCIAL PROJECTIONS. Effective on the Effective Date of this
Amendment provided for in section 4 hereof, section 7.8 of the Credit Agreement
is amended by deleting the sentence:

         No facts are known to the Company at the date hereof which, if
         reflected in the Financial Projections, would result in a material
         adverse change in the assets, liabilities, results of operations or
         cash flows reflected therein.

and inserting in its place the sentence:

         No facts are known to the Company at the date hereof which, if
         reflected in the Recent Financial Projections, would result in a
         material adverse change in the assets, liabilities, results of
         operations or cash flows reflected therein.

         1.5. NO MATERIAL ADVERSE CHANGE. Effective on the Effective Date of
this Amendment provided for in section 4 hereof, section 7.9 of the Credit
Agreement is amended to read in its entirety as follows:

                  7.9. NO MATERIAL ADVERSE CHANGE. Since December 31, 1999,
         there has been no change in the condition, business or affairs of the
         Company and its Subsidiaries taken as a whole, or their properties and
         assets considered as an entirety, except for changes, none of which,
         individually or in the aggregate, has had or could reasonably be
         expected to have, a Material Adverse Effect, other than changes in the
         condition, business or affairs of the Company reflected in the Recent
         Financial Projections.

         1.6. REPORTING REQUIREMENTS. If this Amendment becomes effective as
provided in section 4 hereof, then effective as of January 1, 2000, section
8.1(b) of the Credit Agreement is amended by deleting the text "As soon as
available and in any event within 45 days after the close of each of the
quarterly accounting periods in each fiscal year of the Company," and inserting
in its place the text "As soon as available and in any event within 45 days
after the close of each of the first three quarterly accounting periods and
within 90 days after the close of the final quarter of the quarterly accounting
periods in each fiscal year of the Company".

         1.7. INTEREST COVERAGE RATIO. If this Amendment becomes effective as
provided in section 4 hereof, then effective as of September 30, 1999 and at all
times thereafter, section 9.7 of the Credit Agreement and the reference thereto
in section 9.4 of the Credit Agreement shall be of no further force or effect.

         1.8. LEVERAGE COVENANT. Effective on the Effective Date of this
Amendment provided for in section 4 hereof, section 9.6 of the Credit Agreement
is amended to read in its entirety as follows:

                  9.6. RATIO OF CONSOLIDATED SENIOR INDEBTEDNESS TO CONSOLIDATED
         TOTAL CAPITALIZATION. The Company will not at any time permit the ratio
         of (i) its Consolidated Senior Indebtedness at such time, to (ii) its
         Consolidated Total Capitalization at such time, expressed as a
         percentage, to exceed 70.00%, PROVIDED, HOWEVER, during the period from
         December 31, 1999 to June 30, 2000, so long as the Company is in
         compliance with section 9.12 hereof during such period, such ratio
         expressed as a percentage shall not exceed 73.00%.

         1.9. MINIMUM CONSOLIDATED NET WORTH. Effective on the Effective Date of
this Amendment provided for in section 4 hereof, section 9.5 of the Credit
Agreement is amended by deleting the text:

         (ii) the foregoing amount (as it may from time to time be increased as
         herein provided), shall be increased by an amount equal to 75% of the
         cash proceeds (net of underwriting discounts and



                                       3
<PAGE>   4

         commissions and other customary fees and costs associated therewith)
         from any sale or issuance of equity by the Company after March 31, 1998
         (other than any sale or issuance to any Subsidiary or to management or
         employees pursuant to employee benefit plans of general application),

and inserting in its place the text:

         (ii) the foregoing amount (as it may from time to time be increased as
         herein provided), shall be increased by an amount equal to 75% of the
         cash proceeds (net of underwriting discounts and commissions and other
         customary fees and costs associated therewith) from any sale or
         issuance of equity by the Company after March 31, 1998 (other than any
         sale or issuance to any Subsidiary or to management or employees
         pursuant to employee benefit plans of general application), including,
         without limitation, 75% of the net cash proceeds received by the
         Company pursuant to the satisfaction of the New Capital Funding
         Requirement,

         1.10. CONSOLIDATED EBIT. Effective on the Effective Date of this
Amendment provided for in section 4 hereof, the definition of Consolidated EBIT
contained in section 1.1 of the Credit Agreement is amended to read in its
entirety as follows:

                  "CONSOLIDATED EBIT" shall mean, for any period, Consolidated
         Net Income for such period, PLUS (A) the sum of the amounts for such
         period included in determining such Consolidated Net Income of (i)
         Consolidated Interest Expense, (ii) Consolidated Income Tax Expense,
         and (iii) extraordinary and other non-recurring non-cash losses and
         charges, LESS (B) gains on sales of assets and other extraordinary
         gains and other non-recurring non-cash gains, all as determined for the
         Company and its Subsidiaries on a consolidated basis in accordance with
         GAAP.

         1.11. EVENTS OF DEFAULT. Effective on the Effective Date of this
Amendment provided for in section 4 hereof, sections 10.1(c) and (k) of the
Credit Agreement are amended to read in their entirety as follows:

                  (c) CERTAIN NEGATIVE COVENANTS: the Company shall default in
         the due performance or observance by it of any term, covenant or
         agreement contained in sections 9.3, 9.4, 9.5, 9.6, 9.7, 9.10, 9.11,
         9.12, 9.13 or 9.14 of this Agreement; or any Borrower shall default in
         the due performance or observance by it of any term, covenant or
         agreement contained in sections 5, 10, 16(a)(i) or 16(c) of any
         Mortgage; or

                  (k) MATERIAL ADVERSE EFFECT: (i) any event or circumstance
         shall occur or exist which has a Material Adverse Effect upon the
         Company, as compared to the business, operations, property, assets,
         liabilities or condition (financial or otherwise) of the Company and
         its Subsidiaries as reflected in the financial statements and the
         Financial Projections referred to in section 7.8 other than changes in
         the condition of the Company reflected in the Recent Financial
         Projections; or

                  (ii) any representation or warranty contained in section 2.6
         of Amendment No. 3 to this Credit Agreement, dated as of March 1, 2000,
         with respected to the Recent Financial Projections referred to therein,
         shall prove to be untrue in any material respect as of the date when
         made or deemed made.

         1.12. ADDITIONAL COVENANTS. Effective on the Effective Date of this
Amendment provided for in section 4 hereof, new sections 9.10 through 9.15 are
added to the Credit Agreement, reading in their entirety as follows:

                                       4
<PAGE>   5

                  9.10. RATIO OF CONSOLIDATED EBITDAR TO CONSOLIDATED LEASE AND
         DEBT SERVICE CHARGES. The Company will not permit the ratio of (i)
         Consolidated EBITDAR for any Testing Period, to (ii) Consolidated Lease
         and Debt Service Charges for such Testing Period to be less than the
         amount indicated below for such Testing Period:

<TABLE>
<CAPTION>
     TESTING PERIOD                                            RATIO
<S>                                                            <C>
     Testing Period consisting of the single fiscal             .85 to 1.00
     quarter ended March 31, 2000

     Testing Period consisting of the two fiscal quarters       .87 to 1.00
     ended June 30, 2000

     Testing Period consisting of the three fiscal              .90 to 1.00
     quarters ended September 30, 2000

     Testing Period ended December 31, 2000                     .95 to 1.00

     Testing Period ended March 31, 2001                       1.00 to 1.00

     Testing Period ended June 30, 2001                        1.05 to 1.00

     Testing Period ended September 30, 2001                   1.15 to 1.00

     Any Testing Period thereafter                             1.25 to 1.00

</TABLE>


                  9.11. MINIMUM CASH & CASH EQUIVALENTS. (a) The Company will
         not permit the aggregate of its unrestricted cash and Cash Equivalents,
         at any time, to be less than $10,000,000, PROVIDED, HOWEVER, that the
         covenant contained in this section 9.11(a) shall be of no further force
         or effect upon the satisfaction of the New Capital Funding Requirement.

                  (b) The Company will not permit the aggregate of its
         unrestricted cash and Cash Equivalents, as of the end of its fiscal
         quarter ended March 31, 2000, or as of the end of any fiscal quarter
         thereafter, to be less than $20,000,000, PROVIDED, HOWEVER, if the
         Closing Date for any of the proposed Projects commonly known as Fresno
         I, Fresno II, Monroe I, Monroe II, Lebanon I, Lebanon II, Bend and
         Glastonbury has not occurred on or before March 31, 2000, then the
         measurement of unrestricted cash and Cash Equivalents as of March 31,
         2000 shall include the actual net amount funded for each such Project
         which has closed as of such date, if any, together with the net amount
         anticipated to be funded for each such remaining Project, as determined
         by the Administrative Agent in its reasonable discretion, PROVIDED,
         FURTHER, that the covenant contained in this section 9.11(b) shall be
         of no further force or effect upon the satisfaction of both (i)
         satisfaction of the New Capital Funding Requirement resulting in gross
         cash proceeds of at least $150,000,000, and (ii) the ratio of (A)
         Consolidated EBITDAR for any fiscal quarter, to (B) Consolidated Lease
         and Debt Service Charges for such fiscal quarter, exceeds 1.20 to 1.00
         for two consecutive fiscal quarters, with the first eligible fiscal
         quarter to be measured hereunder being the fiscal quarter ending March
         31, 2000.

                                       5
<PAGE>   6

                  9.12. ADDITIONAL CAPITAL REQUIREMENTS. (a) The Company will
         obtain and deliver to the Administrative Agent and the Lenders, on or
         before April 20, 2000, a written commitment, from one or more
         financially responsible institutional or strategic investors, for the
         purchase from the Company of (i) shares of capital stock of the Company
         (other than Redeemable Stock), or (ii) subordinated debt securities of
         the Company, with a maturity of at least five years and no sinking fund
         or similar requirements and no cash interest payments, providing for
         subordination of such subordinated debt securities to the Obligations
         on terms satisfactory to the Required Lenders, in either case for gross
         cash proceeds of at least $100,000,000 (the "NEW CAPITAL COMMITMENT
         REQUIREMENT"), which may include, without limitation, the net proceeds
         from a commitment to convert the debt evidenced by the Amended and
         Restated Loan Agreement dated as of February 3, 2000 between the
         Company and RDVEPCO, L.L.C., a Michigan limited liability company, in
         the original principal amount of $15,000,000 as thereafter increased to
         $35,000,000, to shares of capital stock of the Company (other than
         Redeemable Stock) or subordinated debt securities of the Company, with
         a maturity of at least five years and no sinking fund or similar
         requirements and no cash interest payments, providing for subordination
         of such subordinated debt securities to the Obligations on terms
         satisfactory to the Required Lenders, all in an amount not to exceed
         $35,000,000 (the "BRIDGE LOAN CONVERSION").

                  (b) The Company shall have received, on or before June 30,
         2000, gross cash proceeds of at least $100,000,000, from the issuance
         by the Company of (i) shares of its capital stock (other than
         Redeemable Stock), or (ii) subordinated debt securities of the Company
         conforming to the requirements specified above, as contemplated by the
         commitment obtained by the Company which satisfied the New Capital
         Commitment Requirement (the "NEW CAPITAL FUNDING REQUIREMENT"), which
         proceeds may be comprised in part of the net proceeds of the Bridge
         Loan Conversion.

                  9.13. QUARTERLY MINIMUM CONSOLIDATED EBIT. The Company will
         not permit its Consolidated EBIT for any Testing Period to be less than
         the amount indicated below for such Testing Period:

<TABLE>
<CAPTION>
                            FISCAL QUARTER                                QUARTERLY
                                                                           MINIMUM
                                                                      CONSOLIDATED EBIT
<S>                                                                   <C>
          Testing Period consisting of the single fiscal                  $1,321,000
          quarter ended March 31, 2000

          Testing Period consisting of the two fiscal                     $2,539,000
          quarters ended June 30, 2000

          Testing Period consisting of the three fiscal                   $6,781,000
          quarters ended September 30, 2000

          Testing Period ended December 31, 2000                         $14,427,000

          Testing Period ended March 31, 2001                            $26,524,000

          Testing Period ended June 30, 2001                             $42,161,000
</TABLE>

                                       6
<PAGE>   7
<TABLE>
<S>                                                                      <C>
          Testing Period ended September 30, 2001                        $57,702,000

          Testing Period ended December 31, 2001                         $72,013,000
</TABLE>


                  9.14. DISTRIBUTIONS. The Company will not make any
         distributions or other payments to any of its shareholders, in their
         capacity as shareholders other than dividends in stock or other equity
         securities of the Company and non-cash coupons on equity and debt
         securities issued pursuant to the New Capital Commitment Requirement,
         from the Effective Date of this Amendment until such time as the ratio
         of (i) Consolidated EBITDAR for any Testing Period consisting of the
         immediately preceding 4 fiscal quarters, to (ii) Consolidated Lease and
         Debt Service Charges for such Testing Period, shall exceed 1.25 to 1.00
         for such Testing Period, with the first eligible Testing Period to be
         measured hereunder being the 4 fiscal quarters ending March 31, 2000,
         PROVIDED, HOWEVER, no such distributions shall be made prior to
         December 31, 2000.

                  9.15. MOST FAVORED COVENANT STATUS. Should the Company at any
         time after the date hereof, issue or guarantee or amend any
         Indebtedness denominated in U.S. dollars for money borrowed or
         represented by bonds, notes, debentures or similar securities in an
         aggregate amount exceeding $10,000,000, to any lender or group of
         lenders acting in concert with one another, or one or more
         institutional investors, pursuant to a loan agreement, credit
         agreement, note purchase agreement, indenture, guaranty or other
         similar instrument or amendment thereto, which amendment, agreement,
         indenture, guaranty or instrument, includes affirmative or negative
         business or financial covenants (or any events of default or other type
         of restriction which would have the practical effect of any affirmative
         or negative business or financial covenant, including, without
         limitation, any "put" or mandatory prepayment of such Indebtedness upon
         the occurrence of a "change of control") which are applicable to the
         Company, other than those set forth herein or in any of the other
         Credit Documents, the Company shall promptly so notify the
         Administrative Agent and the Lenders and, if the Administrative Agent
         shall so request by written notice to the Company (after a
         determination has been made by the Required Lenders that any of the
         above-referenced documents or instruments contain any such provisions,
         which either individually or in the aggregate, are more favorable to
         the holders of such other Indebtedness than any of the provisions set
         forth herein), the Company, the Administrative Agent and the Lenders
         shall promptly amend this Agreement to incorporate some or all of such
         provisions, in the discretion of the Administrative Agent and the
         Required Lenders, into this Agreement and, to the extent necessary and
         reasonably desirable to the Administrative Agent and the Required
         Lenders, into any of the other Credit Documents, all at the election of
         the Administrative Agent and the Required Lenders.

         1.6 ADDITIONAL DEFINITIONS. Effective on the Effective Date of this
Amendment provided for in section 4 hereof, the following definitions shall be
added to section 1.1 of the Credit Agreement in appropriate alphabetic order:

         "CONSOLIDATED AMORTIZATION EXPENSE" shall mean, for any period, all
amortization expenses of the Company and its Subsidiaries, all as determined for
the Company and its Subsidiaries on a consolidated basis in accordance with
GAAP.

         "CONSOLIDATED DEPRECIATION EXPENSE" shall mean, for any period, all
depreciation expenses of the Company and its Subsidiaries, all as determined for
the Company and its Subsidiaries on a consolidated basis in accordance with
GAAP.

                                       7
<PAGE>   8

         "CONSOLIDATED EBITDAR" shall mean, for any period, Consolidated EBIT
for such period, PLUS the sum for such period of (i) Consolidated Depreciation
Expense, (ii) Consolidated Amortization Expense, and (iii) Consolidated Rental
Expense, all as determined for the Company and its Subsidiaries on a
consolidated basis in accordance with GAAP.

         "CONSOLIDATED LEASE AND DEBT SERVICE CHARGES" shall mean, for any
period, the sum for such period of (i) Consolidated Interest Expense, (ii)
Consolidated Rental Expense, (iii) scheduled or mandatory repayments,
prepayments or redemptions of the principal of Indebtedness and the stated or
liquidation value of Redeemable Stock (including required reductions in
committed credit facilities), and (iv) without duplication of any amount
included under the preceding clause (iii), scheduled payments representing the
principal portion of Capital Leases and Synthetic Leases, all as determined for
the Company and its Subsidiaries on a consolidated basis in accordance with
GAAP.

         "CONSOLIDATED RENTAL EXPENSE" shall mean, for any period, all basic
rental expenses of the Company and its Subsidiaries (exclusive of any thereof
specifically intended to cover taxes, maintenance, insurance or similar
charges), all as determined for the Company and its Subsidiaries on a
consolidated basis in accordance with GAAP, PROVIDED that Consolidated Rental
Expense shall be computed without duplication of any amounts in respect of any
Capital Lease or Synthetic Lease which is included in Consolidated Interest
Expense.

         "NEW CAPITAL COMMITMENT REQUIREMENT" shall have the meaning provided in
section 9.12(a).

         "NEW CAPITAL FUNDING REQUIREMENT" shall have the meaning provided in
section 9.12(b).

         "OPERATING LEASE" as applied to any person shall mean any lease of any
property (whether real, personal or mixed) by that person as lessee which, in
conformity with GAAP, is not accounted for as a Capital Lease on the balance
sheet of that person.

         "SYNTHETIC LEASE" shall mean any lease (i) which is accounted for by
the lessee as an Operating Lease, and (ii) under which the lessee is intended to
be the "owner" of the leased property for Federal income tax purposes.

         SECTION 2. REPRESENTATIONS AND WARRANTIES.

         The Company represents and warrants as follows:

         2.1. AUTHORIZATION AND VALIDITY OF AMENDMENT, ETC. This Amendment has
been duly authorized by all necessary corporate action on the part of the
Company, has been duly executed and delivered by a duly authorized officer of
the Company, and constitutes the valid and binding agreement of the Company,
enforceable against the Company in accordance with its terms, except to the
extent that the enforceability thereof may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium or other similar laws generally affecting
creditors' rights and by equitable principles (regardless of whether enforcement
is sought in equity or at law).

         2.2. REPRESENTATIONS AND WARRANTIES. The representations and warranties
of the Credit Parties contained in the Credit Agreement, as amended hereby, or
in the other Credit Documents are true and correct in all material respects on
and as of the date hereof as though made on and as of the date hereof, except to
the extent that such representations and warranties expressly relate to an
earlier specified date, in which case such representations and warranties are
hereby reaffirmed as true and correct in all material respects as of the date
when made.

                                       8
<PAGE>   9

         2.3. NO EVENT OF DEFAULT. No condition or event has occurred or exists
which constitutes or which, after notice or lapse of time or both, would
constitute an Event of Default under the Credit Agreement as amended hereby, or
under the other Credit Documents.

         2.4. COMPLIANCE. The Company is in full compliance with all covenants
and agreements contained in the Credit Agreement, as amended hereby, and the
other Credit Documents to which it is a party.

         2.5. FINANCIAL STATEMENTS, ETC. The Company has furnished to the
Lenders and the Administrative Agent complete and correct copies of:

                  (a) the audited consolidated balance sheets of the Company and
         its consolidated subsidiaries as of December 31, 1998, and the related
         audited consolidated statements of income, stockholders' equity, and
         cash flows of the Company and its consolidated subsidiaries for the
         fiscal year then ended, accompanied by the unqualified report thereon
         of the Company's independent accountants; and

                  (b) the unaudited consolidated balance sheets of the Company
         and its consolidated subsidiaries as of September 30, 1999, and the
         related unaudited consolidated statements of income, stockholders'
         equity and cash flows of the Company and its consolidated subsidiaries
         for the fiscal quarter or quarters then ended.

All such financial statements have been prepared in accordance with GAAP,
consistently applied (except as stated therein), and fairly present the
financial position of the Company and its consolidated subsidiaries as of the
respective dates indicated and the consolidated results of their operations and
cash flows for the respective periods indicated, subject in the case of any such
financial statements which are unaudited, to the absence of footnotes and to
normal audit adjustments which the Company reasonably believes will not involve
a Material Adverse Effect.

         2.6. RECENT FINANCIAL PROJECTIONS, ETC. The Company delivered or caused
to be delivered to the Lenders, on or about February 3, 2000, financial
projections prepared by management of the Company for the Company and its
Subsidiaries consisting of, among other things, a projected balance sheet,
income statement and cash flow statement for its fiscal years ended December 31,
1999 through December 31, 2003 (the "RECENT FINANCIAL PROJECTIONS"). The Recent
Financial Projections were prepared on behalf of the Company in good faith after
taking into account the existing and historical levels of business activity of
the Company and its Subsidiaries, trends known to the Company, including general
economic trends, and all other information, assumptions and estimates considered
by management of the Company and its Subsidiaries to be pertinent thereto. The
Recent Financial Projections were considered by management of the Company, as of
such date of preparation, to be realistically achievable; PROVIDED, that no
representation or warranty is made as to the impact of future general economic
conditions or as to whether the Company's projected consolidated results as set
forth in the Recent Financial Projections will actually be realized. No material
facts have become known to the Company subsequent to the date of preparation of
the Recent Financial Projections and prior to the date hereof which, if they had
been appropriately reflected in the Recent Financial Projections, would have
resulted in a material adverse change in the assets, liabilities, results of
operations or cash flows reflected therein.

         SECTION 3. RATIFICATIONS.

         Except as expressly modified and superseded by this Amendment, the
terms and provisions of the Credit Agreement are ratified and confirmed and
shall continue in full force and effect.


                                       9
<PAGE>   10

         SECTION 4. BINDING EFFECT.

         This Amendment shall become effective on a date (the "EFFECTIVE DATE"),
on or before March 24, 2000, if the following conditions shall have been
satisfied on and as of such date:

                  (a) EXECUTION OF AMENDMENT. This Amendment shall have been
         executed by the Company and the Administrative Agent, and counterparts
         hereof as so executed shall have been delivered to the Administrative
         Agent; and the Administrative Agent shall have been notified by the
         Required Lenders that such Lenders have executed this Amendment (which
         notification may be by facsimile or other written confirmation of such
         execution).

                  (b) SUPPLEMENTAL RESERVE. Amendment No. 1 to Supplemental
         Reserve Pledge Agreement shall have been executed by the Company and
         the Collateral Agent, and counterparts thereof as so executed shall
         have been delivered to the Administrative Agent.

                  (c) FEES. The Company shall have paid to the Administrative
         Agent, in immediately available funds, for the pro rata account of the
         Lenders who become a signatory hereto on or prior to the date
         established by the Administrative Agent, such nonrefundable amendment
         fees as have previously been agreed to by the Company and communicated
         to the Lenders (the Administrative Agent shall promptly distribute to
         such Lender its pro rata portion of such amendment fees).

Thereafter this Amendment shall be binding upon and inure to the benefit of the
Company, the Administrative Agent, and each Lender and their respective
permitted successors and assigns. After this Amendment becomes effective, the
Administrative Agent will promptly furnish a copy of this Amendment and
Amendment No. 1 to Supplemental Reserve Pledge Agreement to each Lender and the
Company and advise them of the Effective Date.

         SECTION 5. MISCELLANEOUS.

         5.1. SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations
and warranties made in this Amendment shall survive the execution and delivery
of this Amendment, and no investigation by the Administrative Agent or any
Lender or any subsequent Loan shall affect the representations and warranties or
the right of the Administrative Agent or any Lender to rely upon them.

         5.2. REFERENCE TO CREDIT AGREEMENT. The Credit Agreement and any and
all other agreements, instruments or documentation now or hereafter executed and
delivered pursuant to the terms of the Credit Agreement as amended hereby, are
hereby amended so that any reference therein to the Credit Agreement shall mean
a reference to the Credit Agreement as amended hereby.

         5.3. EXPENSES. As provided in the Credit Agreement, but without
limiting any terms or provisions thereof, the Company shall pay on demand all
reasonable costs and expenses incurred by the Administrative Agent in connection
with the preparation, negotiation, and execution of this Amendment, including
without limitation the reasonable costs and fees of the Administrative Agent's
special legal counsel, regardless of whether this Amendment becomes effective in
accordance with the terms hereof, and all reasonable costs and expenses incurred
by the Administrative Agent or any Lender in connection with the enforcement or
preservation of any rights under the Credit Agreement, as amended hereby.

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<PAGE>   11

         5.4. SEVERABILITY. Any term or provision of this Amendment held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Amendment and the effect thereof shall be
confined to the term or provision so held to be invalid or unenforceable.

         5.5. APPLICABLE LAW. This Amendment shall be governed by and construed
in accordance with the laws of the State of Ohio.

         5.6. HEADINGS. The headings, captions and arrangements used in this
Amendment are for convenience only and shall not affect the interpretation of
this Amendment.

         5.7. ENTIRE AGREEMENT. This Amendment is specifically limited to the
matters expressly set forth herein. This Amendment and all other instruments,
agreements and documentation executed and delivered in connection with this
Amendment embody the final, entire agreement among the parties hereto with
respect to the subject matter hereof and supersede any and all prior
commitments, agreements, representations and understandings, whether written or
oral, relating to the matters covered by this Amendment, and may not be
contradicted or varied by evidence of prior, contemporaneous or subsequent oral
agreements or discussions of the parties hereto. There are no oral agreements
among the parties hereto relating to the subject matter hereof or any other
subject matter relating to the Credit Agreement.

         5.8. JURY TRIAL WAIVER. EACH OF THE PARTIES TO THIS AMENDMENT HEREBY
IRREVOCABLY WAIVES ALL RIGHT TO A TRIAL BY JURY IN ANY ACTION, PROCEEDING OR
COUNTERCLAIM ARISING OUT OF OR RELATING TO THIS AMENDMENT, THE OTHER CREDIT
DOCUMENTS OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY. EACH PARTY HERETO
HEREBY (A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER
PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT,
IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER, AND (B)
ACKNOWLEDGES THAT IT AND THE OTHER PARTIES HERETO HAVE BEEN INDUCED TO ENTER
INTO THIS AMENDMENT BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND
CERTIFICATIONS IN THIS SECTION.

         5.9. COUNTERPARTS. This Amendment may be executed by the parties hereto
separately in one or more counterparts, each of which when so executed shall be
deemed to be an original, but all of which when taken together shall constitute
one and the same agreement.


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         IN WITNESS WHEREOF, this Amendment has been duly executed and delivered
as of the date first above written.


ALTERRA HEALTHCARE CORPORATION,              ALS NATIONAL, INC.
formerly known as ALTERNATIVE LIVING
SERVICES, INC.


By: /s/ Mark W. Ohlendorf                    By: /s/ Mark W. Ohlendorf
    ------------------------------               ------------------------------
          Senior Vice President                        Vice President



KEY CORPORATE CAPITAL INC.,                  COMERICA BANK
     individually as a lender and
     as administrative agent
                                             By:  /s/ Charles L. Weddell
                                                  -----------------------------
                                                       Vice President
By: /s/
    ------------------------------
          Vice President


BANK OF AMERICA, NATIONAL ASSOCIATION,       U. S. BANK
as successor to BANK OF AMERICA NATIONAL
TRUST AND SAVINGS ASSOCIATION,
  individually as a lender and as co-agent
                                             By: /s/
                                                 ------------------------------
                                                       Vice President
By: /s/
    ------------------------------
          Vice President


SOUTHTRUST BANK, NATIONAL                    BANK ONE, TEXAS, N. A.
ASSOCIATION,
  individually as a lender and as co-agent

                                             By: /s/ Jeffrey A. Etter
                                                 ------------------------------
By: /s/                                                Senior Vice President
    ------------------------------
          Vice President


FLEET NATIONAL BANK


By: /s/ Mary L. Sheehan
    ------------------------------
          Vice President




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