<PAGE>   1




                                                                   EXHIBIT 10.57



                               SECOND AMENDMENT TO

                   PROVISIONAL WAIVER AND STANDSTILL AGREEMENT


         THIS SECOND AMENDMENT TO PROVISIONAL WAIVER AND STANDSTILL AGREEMENT
(this "Second Amendment") is made and entered into as of the 14th day of July,
2000, by the Lenders party to the Credit Agreement identified below and FIRST
UNION NATIONAL BANK, as Agent for the Lenders, and RURAL/METRO CORPORATION, a
corporation organized under the laws of Delaware (the "Borrower").

                              Statement of Purpose

         Pursuant to the Provisional Waiver and Standstill Agreement dated as of
March 14, 2000 (as amended, restated, supplemented or otherwise modified, the
"Waiver Agreement"), the Borrower, the Agent and the Lenders, each a party to
the Amended and Restated Credit Agreement dated as of March 16, 1998 (as amended
by the First Amendment dated as of June 30, 1998 and as further amended,
restated, supplemented or otherwise modified, the "Credit Agreement"), agreed to
waive the Acknowledged Defaults provisionally for a period of 30 days after
March 14, 2000 and to defer the exercise of remedies during such period, subject
to the express terms and provisions of the Waiver Agreement.

         Pursuant to the First Amendment to the Provisional Waiver and
Standstill Agreement dated as of April 13, 2000 (the "First Amendment"), the
Borrower, the Lenders and the Agent agreed, among other things, to continue to
waive the Acknowledged Defaults provisionally until July 14, 2000, or earlier if
certain other specified events occur, and to continue negotiations with the
Agent and the Lenders to amend or otherwise restructure the Credit Agreement.
The Borrower, the Agent and the Lenders are continuing to negotiate but have not
yet reached an agreement on such amendment or restructuring and the Borrower
has, therefore, requested an additional period of time in which to continue such
negotiations.

         The Lenders and the Agent are willing to continue to waive the
Acknowledged Defaults provisionally for an additional period of time and to
defer the exercise of remedies in respect of the Acknowledged Defaults during
such period subject to the express terms and provisions of this Second
Amendment. This Second Amendment shall be deemed to be one of the Loan Documents
under and pursuant to the Credit Agreement.

         NOW THEREFORE, in consideration of the premises and the mutual
covenants contained herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree as follows:
<PAGE>   2

         1. Effect of Amendment and Acknowledgments by Borrower. Except as
expressly amended hereby, the First Amendment, the Waiver Agreement, the Credit
Agreement and each other Loan Document, shall be and remain in full force and
effect. The amendments granted in this Second Amendment are specific and limited
and shall not constitute a modification, acceptance or waiver of any other
provision of the First Amendment, the Waiver Agreement, the Credit Agreement,
the other Loan Documents or any other document or instrument entered into in
connection therewith, or a future modification, acceptance or waiver of the
provisions set forth therein. For avoidance of doubt, but in no way limiting the
scope and breadth of the previous sentences in this paragraph, each Credit Party
hereby reaffirms each of the acknowledgments and agreements made by it in
Sections 1 (except as expressly amended in Paragraph 3(a) below), 6 and 7 of the
Waiver Agreement as if each such acknowledgment and agreement was made as of the
date hereof.

         2. Capitalized Terms. All capitalized undefined terms used in this
Second Amendment shall have the meanings assigned thereto in the Waiver
Agreement.

         3. Amendment of Waiver Agreement. The Waiver Agreement shall be hereby
amended as follows:

         a. Section 1 shall hereby be amended by deleting paragraph 1(c) and
replacing it in its entirety with the following:

                  "(c) The Loans outstanding as of the date hereof are in an
         amount equal to $146,559,153.00 (the "Existing Loans") and the L/C
         Obligations outstanding as of the date hereof are in an amount equal to
         $6,515,000.00 (the "Existing L/C Obligations", and together with the
         Existing Loans, the "Existing Extensions of Credit") and no Credit
         Party has any defense or right of offset with respect to such amounts."

         b. Section 2 shall hereby be amended by deleting Section 2 and
replacing it in its entirety with the following:

                  "Provisional Waiver and Limited Deferral. The Lenders and the
         Agent respectively agree to waive the Acknowledged Defaults
         provisionally and to defer the exercise of any rights or remedies
         arising by reason of Events of Default that have occurred solely as a
         result of the occurrence of the Acknowledged Defaults until that date
         (as so extended and as may be further extended, the "Waiver Maturity
         Date") which is the earliest to occur of (a) October 16, 2000; (b) the
         occurrence of any Event of Default other than (i) the Acknowledged
         Defaults or (ii) any breach of the financial covenants that are the
         subject of the Acknowledged Defaults as of the fiscal quarters ending
         March 31, 2000, June 30, 2000 and September 30, 2000; (c) any Event of
         Default (as such term is defined in the Senior Note Indenture (as
         defined below)) that shall have occurred under the Indenture dated as
         of March 16, 1998, by and among the Borrower, the subsidiaries acting
         as Guarantors thereto, and U.S. Bank National Association, a national
         banking association, successor to the First National Bank of Chicago,
         as Trustee (the "Senior Note


                                      -2-
<PAGE>   3
         Indenture"); or (d) the breach of any of the further conditions or
         agreements provided in the Waiver Agreement as amended by the First
         Amendment and this Second Amendment, it being agreed that the breach of
         any such further condition or agreement shall constitute an immediate
         Default and Event of Default under the Credit Agreement."

         c. Section 3 shall hereby be amended by deleting paragraph 3(b)(i) and
replacing it in its entirety with the following:

            "(i) The Aggregate Commitment shall hereafter be further reduced and
         the Existing Loans repaid by an amount equal to: (A) one hundred
         percent (100%) of the gross cash proceeds, net of all reasonable costs
         of sale and taxes paid or payable as a result thereof by the Borrower
         and its Subsidiaries and net of such other liabilities, costs and
         expenses as are reasonably acceptable to the Agent and the Lenders,
         from the sale or other disposition of assets by the Borrower or any of
         its Subsidiaries from and after March 14, 2000 (including any
         Borrower's or its Subsidiary's equity ownership in any Person), (B) one
         hundred percent (100%) of the gross cash proceeds received by the
         Borrower or any of its Subsidiaries in connection with the Disputed
         Receivables (as defined below), and (C) one hundred percent (100%) of
         the gross cash proceeds received by the Borrower or any of its
         Subsidiaries from any and all receivables from their respective
         business operations wherever located which the Borrower elects to
         shutdown at its option (net of expenses, termination costs, costs of
         professionals and other direct costs related to the shutdown of such
         business operations, which expenses shall include severance and other
         employee-related expenses in respect of the shutdown of such business
         operations and payment of open accounts payable balances subsequently
         paid or payable by Borrower or any of its Subsidiaries in respect of
         such business operations for which services were rendered prior to such
         shutdown); provided that (I) any and all receivables generated by the
         Fort Worth, Texas operations shall be excluded from the requirements
         set forth in this clause (C) and (II) Disputed Receivables shall be
         excluded from the requirements set forth in this clause (C) and subject
         to the requirements set forth in clause (B) above. Notwithstanding the
         foregoing, (X) up to an aggregate amount of two million ($2,000,000)
         dollars of the gross cash proceeds (the "Carve Out") realized upon any
         disposition of assets or shutdown of operations set forth in the
         preceding clauses (A) and (C), net of the expenses and costs referred
         to in the preceding clauses (A) and (C), shall be exempt from this
         paragraph 3(b)(i), and (Y) the Borrower agrees that this provision
         shall not be deemed to permit the sale of assets not otherwise
         permitted under the Credit Agreement. All reductions and prepayments
         set forth in this paragraph shall be made immediately upon receipt of
         the applicable cash proceeds and, for any transactions subject to
         clause (C) of this paragraph 3(b)(i), the identification of any
         applicable adjustments to such proceeds; provided, that all adjustments
         to any proceeds received by the Borrower or its Subsidiaries shall be
         completed, and the applicable amounts turned over to the Lenders within
         ten (10) Business Days after the end of the month in which such funds
         are received unless the Lender Financial Consultant agrees to provide
         the Borrower additional time to complete its adjustments. As used
         herein, the term "Disputed Receivables" shall mean those receivables,
         net of reasonable collection costs, if any, disputed with
         Medicare/Medicaid carriers in Texas which were accrued as

                                      -3-
<PAGE>   4
         of December 31, 1999 and which have an aging of no less than 176 days
         past the date of service as of April 30, 2000."

         d. Section 4 shall hereby be amended by deleting paragraph 4(b)(v) and
replacing it in its entirety with the following:

            "(v)        No later than the last day of each calendar week, a
                        written report comparing the actual cash flow of the
                        Borrower and its Subsidiaries during the preceding week
                        to the projected cash balance for such week set forth in
                        the Cash Flow Projection (as defined below), which
                        written report shall be in the form and substance
                        satisfactory to the Lender Financial Consultant,
                        Policano & Manzo LLP; and"

         e. Section 4 shall hereby be further amended by adding the following
paragraph 4(b)(viii) to the end of paragraph 4(b):

            "(viii)     commencing on August 31, 2000 and no later than the last
                        calendar day of each month thereafter, the Borrower
                        shall submit a written report acceptable in form and
                        substance to the Lender Financial Consultant,
                        calculating the amounts received by the Borrower and its
                        Subsidiaries for the preceding calendar month with
                        respect to the amounts due to the Agent and Lenders
                        pursuant to paragraph 3(b)(i)(C) herein, and such report
                        shall include a reconciliation of net cash proceeds
                        receipts as compared to the final "Phase I Shutdown
                        Plan" presented to the Lender Financial Consultant, the
                        Agent and the Lenders."

         f. Section 4 shall hereby be further amended by deleting paragraphs
4(e), 4(g), 4(h) and 4(j) and replacing them in their entirety with the
following paragraphs 4(e), 4(g), 4(h) and 4(j):

         "(e) Intentionally omitted."

         "(g) Each calendar week, the Borrower and its Subsidiaries shall
maintain a cash balance of no less than fifty percent (50%) of the projected
cash balance for such week set forth in the Cash Flow Projection.

         (h) The amount of disbursements in each two (2) consecutive week period
by the Borrower and its Subsidiaries shall not exceed by more than five percent
(5%) the amount of disbursements for such two (2) week period set forth in the
Cash Flow Projection; provided , that the Borrower and its Subsidiaries may use
the Carve Out or any Excess Cash that is not required to be turned over to the
Lenders to make any additional disbursements; and, provided further, that any
reasonable fees paid to the Investment Banker (as defined below) shall be
excluded from the calculation of the foregoing disbursement."

         "(j) No later than (i) August 12, 2000 the Borrower shall have engaged
an investment banker (the "Investment Banker") for the purpose of identifying
and disposing of

                                      -4-
<PAGE>   5
         non-core business operations of the Borrower and its Subsidiaries , and
         (ii) September 30, 2000 the Investment Banker shall have completed an
         offering memorandum in respect of the sale of such operations. The
         Agent and the Lenders shall be provided with an executed copy of the
         engagement letter between the Borrower and the Investment Banker
         promptly upon such letter's execution. Subject to applicable
         confidentiality agreements, the Agent and the Lenders shall, in
         addition, be provided upon request reasonable access to the Investment
         Banker and shall be further provided with copies of all reports,
         analyses, and other work-product of such Investment Banker when such
         information is delivered to the Borrower."

         g. Section 4 shall hereby be further amended by adding the following
paragraphs 4(k) and 4(l) to the end of Section 4:

            "(k) No later than October 1, 2000, the Borrower on behalf of itself
        and its Subsidiaries shall have completed and delivered a comprehensive
        written proposal for the restructuring of the Debt evidenced by the
        Credit Agreement of the Borrower and its Subsidiaries to the Agent and
        the Lenders.

            (l) No later than October 1, 2000, the Borrower and its Subsidiaries
        shall have completed and delivered their "Phase II Shutdown Plan" to the
        Agent and the Lenders."

         h. Section 9 shall hereby be amended by deleting paragraph 9(a) and
replacing it in its entirety with the following:

            "(a) No later than the date of this Second Amendment, the Borrower
        shall pay to the Agent and the Lenders, for distribution to the Lenders
        pro rata in accordance with their Commitment Percentages, (i) a fee in
        an amount equal to $500,000.00 which fee was fully earned on March 14,
        2000 and (ii) an additional fee in an amount equal to $100,000.00."

         4. Release. Each Credit Party, on behalf of itself and any Person
claiming by, through, or under such Credit Party, acknowledges that it has no
claim, counterclaim, setoff, action or cause of action of any kind or nature
whatsoever ("Claims") against all or any of the Agent, the Lenders or any of the
Agent's or the Lenders' directors, officers, employees, agents, attorneys,
financial advisors, accountants, legal representatives, successors and assigns
(the Agent, the Lenders and their directors, officers, employees, agents,
attorneys, financial advisors, accountants, legal representatives, successors
and assigns are jointly and severally referred to as the "Lender Group"), that
directly or indirectly arise out of or are based upon or in any manner connected
with any "Prior Event" (as defined below), and each Credit Party, on behalf of
itself and any Person claiming by, through or under such Credit Party, hereby
releases the Lender Group from any liability whatsoever should any Claims
nonetheless exist. As used herein the term "Prior Event" means any transaction,
event, circumstances, action, failure to act or occurrence of any sort or type,
whether known or unknown, which occurred, existed, was taken, permitted or begun
prior to the execution of this Second Amendment and occurred, existed, was
taken, permitted or begun in accordance with, pursuant to or by virtue of any
terms of this Second Amendment, the transactions referred to herein, any Loan
Document or oral or written

                                      -5-
<PAGE>   6
agreement relating to any of the foregoing, including without limitation any
approval or acceptance given or denied.

         5. Representations and Warranties. By its execution hereof, the
Borrower hereby certifies on behalf of itself and the other Credit Parties that
each of the representations and warranties set forth in the Credit Agreement and
the other Loan Documents is true and correct as of the date hereof as if fully
set forth herein, and that as of the date hereof no Default or Event of Default
(other than Events of Default occurring as a result of the occurrence of the
Acknowledged Defaults) has occurred and is continuing. Additionally, the
Borrower represents and warrants that, since April 13, 2000, no event which has
had, or could reasonably be expected to have, a Material Adverse Effect has
occurred, except as previously disclosed in writing to the Agent.

         6. Conditions. The effectiveness of this Second Amendment shall be
conditioned upon the following:

         (a) The following documents shall have been duly authorized and
executed by the parties thereto, shall be in full force and effect and no
default shall exist thereunder, and the Borrower shall have delivered original
counterparts thereof the Agent:

             (i)          this Second Amendment, duly executed and delivered by
                          the Credit Parties, the Agent and the Lenders
                          constituting Required Lenders;

             (ii)         a cash flow projection (the "Cash Flow Projection")
                          for the Borrower and its Subsidiaries for each week up
                          through and including October 16, 2000 which shall be
                          attached hereto as Exhibit "A" and which shall be in
                          the form and substance satisfactory to the Lender
                          Financial Consultant; and

             (iii)        such other documents, certificates and instruments as
                          the Agent reasonably requests.

         (b) The Borrower shall have paid all outstanding fees and expenses, to
the extent that the Borrower has received an invoice for such fees and expenses,
through the date hereof of Stroock & Stroock & Lavan LLP and the Lender
Financial Consultant.

         7. Governing Law. THE WAIVER AGREEMENT, AS AMENDED BY THE FIRST
AMENDMENT AND AS AMENDED HEREIN, AND EACH OTHER LOAN DOCUMENT, UNLESS OTHERWISE
EXPRESSLY SET FORTH THEREIN, SHALL BE GOVERNED BY, CONSTRUED AND ENFORCED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NORTH CAROLINA, WITHOUT REFERENCE TO
THE CONFLICTS OR CHOICE OF LAW PRINCIPLES THEREOF.

         8. Miscellaneous.

         a. Reversal of Payments. To the extent the Borrower
makes a payment or payments to the Agent for the ratable benefit of Lenders
pursuant to the Waiver Agreement, as amended by

                                      -6-
<PAGE>   7
the First Amendment and as amended herein, the Notes or any other Loan Document
which payments or proceeds or any part thereof are subsequently invalidated,
declared to be fraudulent or preferential, set aside and/or required to be
repaid to a trustee, receiver or any other party under any bankruptcy law, state
or federal law, common law or equitable cause, then, to the extent of such
payment or proceeds repaid, the Obligations or part thereof intended to be
satisfied shall be revived and continued in full force and effect as if such
payment or proceeds had not been received by the Agent.

         b.       Arbitration.

                              (i) Binding Arbitration. Upon demand of any party,
                  whether made before or after institution of any judicial
                  proceeding, any dispute, claim or controversy arising out of,
                  connected with or relating to the Waiver Agreement, as amended
                  by the First Amendment and as amended herein, the Notes or any
                  other Loan Documents ("Disputes"), between or among parties to
                  this Second Amendment, the Notes or any other Loan Document
                  shall be resolved by binding arbitration as provided herein.
                  Institution of a judicial proceeding by a party does not waive
                  the right of that party to demand arbitration hereunder.
                  Disputes may include, without limitation, tort claims,
                  counterclaims, claims brought as class actions, claims arising
                  from Loan Documents executed in the future, or claims
                  concerning any aspect of the past, present or future
                  relationships arising out or connected with the Loan
                  Documents. Arbitration shall be conducted under and governed
                  by the Commercial Financial Disputes Arbitration Rules (the
                  "Arbitration Rules") of the American Arbitration Association
                  (the "AAA") and Title 9 of the U.S. Code. All arbitration
                  hearings shall be conducted in Charlotte, North Carolina. The
                  expedited procedures set forth in Rule 51, et seq., of the
                  Arbitration Rules shall be applicable to claims of less than
                  $1,000,000. All applicable statutes of limitation shall apply
                  to any Dispute. A judgment upon the award may be entered in
                  any court having jurisdiction. The panel from which all
                  arbitrators are selected shall be comprised of licensed
                  attorneys. The single arbitrator selected for expedited
                  procedure shall be a retired judge from the highest court of
                  general jurisdiction, state or federal, of the state where the
                  hearing will be conducted. The arbitrators shall be appointed
                  as provided in the Arbitration Rules.

                              (ii) Preservation of Certain Remedies.
                  Notwithstanding the preceding binding arbitration provisions,
                  the Agent and the Lenders preserve, without diminution,
                  certain remedies that the Agent and the Lenders may employ or
                  exercise freely, either alone, in conjunction with or during a
                  Dispute. The Agent and the Lenders shall have and hereby
                  reserve the right to proceed in any court of proper
                  jurisdiction or by self help to exercise or prosecute the
                  following remedies: (A) all rights to foreclose against any
                  real or personal property or other security by exercising a
                  power of sale granted in the Loan Documents or under
                  applicable law or by judicial foreclosure and sale, (B) all
                  rights of self help including peaceful occupation of property
                  and collection of rents, set off, and peaceful possession of
                  property and (C) obtaining provisions or ancillary remedies
                  including injunctive

                                      -7-
<PAGE>   8
                  relief, sequestration, garnishment, attachment, appointment of
                  receiver and in filing an involuntary bankruptcy proceeding.
                  Preservation of these remedies does not limit the power of any
                  arbitrator to grant similar remedies that may be requested by
                  a party in a Dispute.

         c. Waiver of Jury Trial. TO THE EXTENT PERMITTED BY APPLICABLE LAW, THE
AGENT, EACH LENDER AND THE BORROWER HEREBY IRREVOCABLY WAIVE THEIR RESPECTIVE
RIGHTS TO A JURY TRIAL WITH RESPECT TO ANY ACTION, CLAIM OR OTHER PROCEEDING
ARISING OUT OF ANY DISPUTE IN CONNECTION WITH THE WAIVER AGREEMENT, AS AMENDED
BY THE FIRST AMENDMENT AND AS AMENDED HEREIN, THE NOTES OR THE OTHER LOAN
DOCUMENTS, ANY RIGHTS OR OBLIGATIONS HEREUNDER OR THEREUNDER, OR THE PERFORMANCE
OF SUCH RIGHTS AND OBLIGATIONS.

         d. Survival of Terms of Agreement. The waivers, agreements, covenants,
representations and warranties of each Credit Party in the Waiver Agreement, as
amended by the First Amendment and as amended herein, shall survive the Waiver
Maturity Date.

         9. Counterparts. This Second Amendment may be executed in separate
counterparts, each of which when executed and delivered is an original but all
of which taken together constitute one and the same instrument.


                            [Signature pages follow]

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<PAGE>   9
         IN WITNESS WHEREOF, the parties hereto have caused this Second
Amendment to be duly executed as of the date and year first above written.

                                    BORROWER:

                                    RURAL/METRO CORPORATION, a Delaware
                                         corporation

                                    By:/s/ John S. Banas III
                                       ---------------------
                                    Name:  John S. Banas III
                                        ---------------------
                                    Title: Senior Vice President and
                                           -------------------------
                                           General Counsel




                            [Signature pages follow]


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<PAGE>   10




                                    LENDERS:

                                    FIRST UNION NATIONAL BANK,
                                    as Agent and Lender

                                    By:/s/Ron R. Ferguson
                                         ------------------------
                                    Name: Ron R. Ferguson
                                         ------------------------
                                    Title:Senior Vice President
                                         ------------------------




                            [Signature pages follow]


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<PAGE>   11






                                      FLEET BANK, N.A., as Lender

                                      By:/s/Vincent Pitts
                                         ------------------------
                                      Name: Vincent Pitts
                                          ------------------------
                                      Title:Vice President
                                           ------------------------




                            [Signature pages follow]




                                      -11-
<PAGE>   12
                                      BANK ONE, NA, as Lender

                                      By:  /s/ Bonnie D. Wilson
                                         ------------------------
                                      Name:    Bonnie D. Wilson
                                         ------------------------
                                      Title:   1st Vice President
                                         ------------------------


                            [Signature pages follow]



                                      -12-
<PAGE>   13
                                       ABN AMRO BANK NV, as Lender

                                       By:  /s/ S.L. Wimpenny
                                            --------------------------
                                       Name:    S.L. Wimpenny
                                            --------------------------
                                       Title:   GSVP
                                            --------------------------

                                       By:  /s/William J. Teresky, Jr.
                                            --------------------------
                                       Name:   William J. Teresky, Jr.
                                            --------------------------
                                       Title:  Vice President
                                            --------------------------

                            [Signature pages follow]



                                      -13-
<PAGE>   14



                                     WELLS FARGO BANK, as Lender


                                     By:/s/Art Brokx
                                        -------------------
                                     Name: Art Brokx
                                        -------------------
                                     Title:Vice President
                                        -------------------



                            [Signature pages follow]


                                      -14-
<PAGE>   15

                                       GENERAL ELECTRIC CAPITAL
                                           CORPORATION, as Lender


                                       By:  Thomas E. Johnstone
                                       ---------------------------------
                                       Name:Thomas E. Johnstone
                                       ---------------------------------
                                       Title:Duly Authorized Signatory
                                       ---------------------------------




                            [Signature pages follow]


                                      -15-
<PAGE>   16
                                         BANK OF AMERICA NATIONAL TRUST AND
                                               SAVINGS ASSOCIATION, as Lender


                                         By:    Kurt A. Huisman
                                              -----------------
                                         Name:  Kurt A. Huisman
                                              -----------------
                                         Title: Vice President
                                              -----------------




                            [Signature pages follow]


                                      -16-
<PAGE>   17
                                          BNP PARIBAS, as Lender


                                          By:    Don L. Unruh
                                                 --------------------
                                          Name:  Don L. Unruh
                                                 --------------------
                                          Title: Vice President
                                                 --------------------


                                          By:    Albert A. Young, Jr.
                                                 --------------------
                                          Name:  Albert A. Young, Jr.
                                                 --------------------
                                          Title: Director
                                                 --------------------

                                      -17-
<PAGE>   18
By execution hereof, the undersigned Subsidiary Guarantors hereby acknowledge
and agree to the terms hereof; hereby reaffirm their respective obligations
under the Subsidiary Guaranty and the Intercompany Subordination Agreement;
acknowledge that the Guaranty Obligations with respect to the Subsidiary
Guaranty include the obligations under this Second Amendment; acknowledge that
the Senior Debt as defined in and with respect to the Intercompany Subordination
Agreement include the obligations under this Second Amendment; and hereby agree
that the terms of the Subsidiary Guaranty shall remain in full force and effect
notwithstanding any event or condition which has occurred.

ACCEPTED AND AGREED TO AS OF JULY 14, 2000.
AID AMBULANCE AT VIGO COUNTY, INC., an Indiana corporation, AMBULANCE TRANSPORT
SYSTEMS, INC., a New Jersey corporation, AMERICAN LIMOUSINE SERVICE, INC., an
Ohio corporation, ARROW AMBULANCE, INC., an Idaho corporation, BEACON
TRANSPORTATION, INC., a New York corporation, COASTAL EMS, INC., a Georgia
corporation, CORNING AMBULANCE SERVICE INC., a New York corporation, DONLOCK,
LTD., a Pennsylvania corporation, E.M.S. VENTURES, INC., a Georgia corporation,
EMS VENTURES OF SOUTH CAROLINA, INC., a South Carolina corporation, EASTERN
AMBULANCE SERVICE, INC., a Nebraska corporation, EASTERN PARAMEDICS, INC., a
Delaware corporation, GOLD CROSS AMBULANCE SERVICES, INC., a Delaware
corporation, GOLD CROSS AMBULANCE SERVICE OF PA., INC., an Ohio corporation,
KEEFE & KEEFE, INC., a New York corporation, KEEFE & KEEFE AMBULETTE, LTD., a
New York corporation, LASALLE AMBULANCE INC., a New York corporation, MEDI-CAB
OF GEORGIA, INC., a Delaware corporation, MEDICAL EMERGENCY DEVICES AND SERVICES
(MEDS), INC., an Arizona corporation, MEDICAL TRANSPORTATION SERVICES, INC., a
South Dakota corporation, MEDSTAR EMERGENCY MEDICAL SERVICES, INC., a Delaware
corporation, MERCURY AMBULANCE SERVICE, INC., a Kentucky corporation, METRO CARE
CORP., an Ohio corporation, MO-RO-KO, INC., an Arizona corporation, MULTI CAB
INC., a New Jersey corporation, MULTI-CARE INTERNATIONAL, INC., a New Jersey
corporation, MULTI-CARE MEDICAL CAR SERVICE, INC., a New Jersey corporation,
MULTI-HEALTH CORP., a Florida corporation, MYERS AMBULANCE SERVICE, INC., an
Indiana corporation, NATIONAL AMBULANCE & OXYGEN SERVICE, INC., a New York
corporation, NORTH MISS. AMBULANCE SERVICE, INC., a Mississippi corporation,
PROFESSIONAL MEDICAL SERVICES, INC., an Arkansas corporation, RISC AMERICA
ALABAMA FIRE SAFETY SERVICES, INC., a Delaware corporation, RMFD OF NEW JERSEY,
INC., a Delaware corporation, R/M MANAGEMENT CO., INC., an Arizona corporation,
R/M OF MISSISSIPPI, INC., a Delaware corporation, R/M OF TENNESSEE G.P., INC., a
Delaware corporation, R/M OF TENNESSEE L.P., INC., a Delaware corporation, R/M
OF TEXAS G.P., INC., a Delaware corporation, R/M PARTNERS, INC., a Delaware
corporation, RMC CORPORATE CENTER, L.L.C., an Arizona limited liability company,
By: RURAL/METRO CORPORATION, an Arizona corporation, Its Member, RURAL/METRO
ARGENTINA, L.L.C., an Arizona limited liability company, By: RURAL/METRO
INTERNATIONAL, INC., a Delaware corporation, Its Member, RURAL/METRO BRASIL,
L.L.C., an Arizona limited liability company, By: RURAL/METRO INTERNATIONAL,
INC., a Delaware corporation, Its Member, RURAL/METRO CANADIAN HOLDINGS, INC., a
Delaware corporation, RURAL/METRO COMMUNICATIONS SERVICES, INC., a Delaware
corporation, RURAL/METRO CORPORATION, an Arizona corporation, RURAL/METRO
CORPORATION OF FLORIDA, a Florida corporation, RURAL/METRO CORPORATION OF
TENNESSEE, a Tennessee corporation, RURAL/METRO FIRE DEPT., INC., an Arizona
corporation, RURAL/METRO HOSPITAL SERVICES, INC., a Delaware corporation


                                                By:/s/ John S. Banas III
                                                       -----------------
                                                Name:  John S. Banas III
                                                       -----------------
                                                Title: Secretary
                                                       -----------------


                                      -18-
<PAGE>   19
RURAL/METRO INTERNATIONAL, INC., a Delaware corporation, RURAL/METRO LOGISTICS,
INC., a Delaware corporation, RURAL/METRO MID-ATLANTIC, INC., a Delaware
corporation, RURAL/METRO MID-SOUTH, L.P., a Delaware limited partnership, By:
R/M OF TENNESSEE G.P., INC., a Delaware corporation, Its General Partner,
RURAL/METRO OF ALABAMA, INC., a Delaware corporation, RURAL/METRO OF ARGENTINA,
INC., a Delaware corporation, RURAL/METRO OF ARKANSAS, INC., a Delaware
corporation, RURAL/METRO OF ARLINGTON, INC., a Delaware corporation, RURAL/METRO
OF BRASIL, INC., a Delaware corporation, RURAL/METRO OF CALIFORNIA, INC., a
Delaware corporation, RURAL/METRO OF CENTRAL ALABAMA, INC., a Delaware
corporation, RURAL/METRO OF CENTRAL COLORADO, INC., a Delaware corporation,
RURAL/METRO OF CENTRAL OHIO, INC., a Delaware corporation, RURAL/METRO OF
COLORADO, a Delaware corporation, RURAL/METRO OF GEORGIA, INC., a Delaware
corporation, RURAL/METRO OF GREATER SEATTLE, INC., a Washington corporation,
RURAL/METRO OF INDIANA, INC., a Delaware corporation, RURAL/METRO OF INDIANA,
L.P., a Delaware limited partnership, By: THE AID AMBULANCE COMPANY, INC., a
Delaware corporation, Its General Partner, RURAL/METRO OF INDIANA II, L.P., a
Delaware limited partnership, By: THE AID AMBULANCE COMPANY, INC., a Delaware
corporation, Its General Partner, RURAL/METRO OF KENTUCKY, INC., a Delaware
corporation, RURAL/METRO OF MISSISSIPPI, INC., a Delaware corporation,
RURAL/METRO OF NEBRASKA, INC., a Delaware corporation, RURAL/METRO OF NEVADA,
INC., a Delaware corporation, RURAL/METRO OF NEW YORK, INC., a Delaware
corporation, RURAL/METRO OF NORTH FLORIDA, INC., a Florida corporation,
RURAL/METRO OF NORTH TEXAS, L.P., By: R/M OF TEXAS G.P., INC., a Delaware
corporation, Its General Partner, RURAL/METRO OF NORTHERN OHIO, INC., a Delaware
corporation, RURAL/METRO OF OHIO, INC., a Delaware corporation, RURAL/METRO OF
OREGON, INC., a Delaware corporation, RURAL/METRO OF ROCHESTER, INC., a New York
corporation, RURAL/METRO OF SAN DIEGO, INC., a California corporation,
RURAL/METRO OF SOUTH CAROLINA, INC., a Delaware corporation, RURAL/METRO OF
SOUTH DAKOTA, INC., a Delaware corporation, RURAL/METRO OF SOUTHERN OHIO, INC.,
an Ohio corporation, RURAL/METRO OF TENNESSEE, L.P., a Delaware limited
partnership, By: R/M OF TENNESSEE G.P., INC., a Delaware corporation, Its
General Partner, RURAL/METRO OF TEXAS, INC., a Delaware corporation, RURAL/METRO
OF TEXAS, L.P., a Delaware limited partnership, By: R/M OF TEXAS G.P., INC., a
Delaware corporation, Its General Partner, RURAL/METRO PROTECTION SERVICES,
INC., an Arizona corporation, RURAL/METRO TEXAS HOLDINGS, INC., a Delaware
corporation, SW GENERAL, INC., an Arizona corporation, SIOUX FALLS AMBULANCE,
INC., a South Dakota corporation, SOUTH GEORGIA EMERGENCY MEDICAL SERVICES,
INC., a Georgia corporation, SOUTHWEST AMBULANCE AND RESCUE OF ARIZONA, INC., an
Arizona corporation, SOUTHWEST AMBULANCE OF CASA GRANDE, INC., an Arizona
corporation, SOUTHWEST AMBULANCE OF TUCSON, INC., an Arizona corporation,
SOUTHWEST GENERAL SERVICES, INC., an Arizona corporation, THE AID AMBULANCE
COMPANY, INC., a Delaware corporation, THE AID COMPANY, INC., an Indiana
corporation, TOWNS AMBULANCE SERVICE, INC., a New York corporation, VALLEY FIRE
SERVICE, INC., a Delaware corporation, W & W LEASING COMPANY, INC., an Arizona
corporation

                                                 By:  /s/ John S. Banas III
                                                       --------------------
                                                 Name:  John S. Banas III
                                                       --------------------
                                                 Title:  Secretary
                                                       --------------------


                                      -19-
<PAGE>   20

                                    EXHIBIT A
                                    ---------

                          FORM OF CASH FLOW PROJECTION
                          ----------------------------


                                      -20-