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                                                            EXHIBIT 10.18

                               SECOND AMENDMENT
                                    TO THE
                          RENTAL SERVICE CORPORATION
                          FIRST AMENDED AND RESTATED
                    EMPLOYEE QUALIFIED STOCK PURCHASE PLAN

     The shareholders of Rental Service Corporation (the "Company") previously
approved the adoption of the Rental Service Corporation First Amended and
Restated Employee Qualified Stock Purchase Plan (the "Q.S.P. Plan") to assist
employees of the Company in acquiring stock ownership interests in the Company.
By this instrument, the Company desires to amend the Q.S.P. Plan to clarify that
the Company originally intended to designate sales commissions as an item
included in the definition of "Base Pay" under the Q.S.P. Plan and to permit
participants who discontinue participating in the Q.S.P. Plan during an Offering
Period the option of withdrawing funds contributed to the Q.S.P. Plan during the
Offering Period or leaving such amounts in the Q.S.P. Plan until the end of the
Offering Period.  The Company therefore and hereby adopts this Amendment to
Rental Service Corporation First Amended and Restated Qualified Stock Purchase
Plan as set forth below pursuant to Section 16 of the Q.S.P. Plan.

     1.   This Amendment shall amend only those Sections specified herein and
          those Sections not amended hereby shall remain in full force and
          effect.

     2.   The provisions of this Amendment shall be effective as set forth
          below.

     3.   Effective as of the effective date of the Q.S.P. Plan, Section 2(b) of
          the Q.S.P. Plan is hereby amended and restated in its entirety as
          follows:

          (b)     "Base Pay" shall mean gross pay received by an Employee on
          each Payday as cash compensation for services to the Company,
          including any sales commissions Employee received by or through the
          Company, but excluding overtime payments, 
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          incentive compensation, bonuses, and other special-payments, except to
          the extent that the inclusion of any such item is specifically
          designated by the Administrator.

     4.   Effective for the Offering Period that began on July 1, 1998, Section
          11(b) of the Plan is hereby amended and restated in its entirety as
          follows:

               (b)   Upon cessation of participation by an Eligible Employee,
          such Eligible Employee's payroll deductions shall cease.  If the
          Eligible Employee ceases to participate due to death, the balance of
          payroll deductions credited to such Eligible Employee's account shall
          be paid or distributed to the executor or administrator of the
          Eligible Employee's estate, and neither the Administrator nor the
          Company shall have any further liability to anyone. Except as provided
          below, if the Eligible Employee ceases to participate for any reason
          other than death, the Eligible Employee has the right to elect, within
          the 30-day period after ceasing to participate (or if earlier the
          first day of the last two weeks before the end of the Offering
          Period), either to (i) have any balance of payroll deductions credited
          to the Eligible Employee's account under the Q.S.P. Plan paid to the
          Employee in cash in one lump sum as soon as practicable after
          cessation of participation, without payment of any interest, or (ii)
          have the balance of payroll deductions credited to the Eligible
          Employee's account under the Q.S.P. Plan remain in such Plan and have
          the Eligible Employee's Option exercised on the last day of the
          Offering Period, in accordance with Section 8(b).  If the Eligible
          Employees fails to make an election, the balance of payroll deductions
          credited to the Eligible Employee's account under the Q.S.P. Plan
          shall be paid to the Employee in cash in one lump sum as soon as
          practicable after the end of the notice period, without payment of any
          interest.  If the Eligible Employee ceases participation within the
          last two weeks of an Offering Period, the balance of payroll
          deductions credited to the Eligible Employee's account under the
          Q.S.P. Plan will remain in such Plan and the Eligible Employee's
          Option will be exercised on the last day of the Offering Period, in
          accordance with Section 8(b).

     5.   This Amendment shall be attached hereto and shall become part of the
          Q.S.P. Plan.

                                 * * * * *
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     I hereby certify that the foregoing Amendment was adopted by the Board of
     Directors of Rental Service Corporation on the 14th day of September, 1998.

                                   RENTAL SERVICE CORPORATION


                                   By: /s/ David B. Harrington
                                       -----------------------
                                   Its: Senior Vice President of Human Resources