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                                                                     Exhibit 4.3

                       FIRST AMENDMENT TO CREDIT AGREEMENT
                       -----------------------------------


         THIS FIRST AMENDMENT TO CREDIT AGREEMENT, dated as of October 19, 2000
(this "Amendment"), is among CORRPRO COMPANIES, INC., an Ohio corporation (the
"Company"), CSI COATING SYSTEMS INC. (the "Canadian Borrower" and together with
the Company, the "Borrowers"), the lenders set forth on the signature pages
hereof (collectively, the "Lenders") and BANK ONE, MICHIGAN, a Michigan banking
corporation, as LC Issuer and as agent for the Lenders (in such capacity, the
"Agent").


                                    RECITALS
                                    --------

         A. The Borrowers, the Agent and the Lenders are parties to a Credit
Agreement dated as of June 9, 2000 (as now and hereafter amended, the "Credit
Agreement"), pursuant to which the Lenders agreed, subject to the terms and
conditions thereof, to extend credit to the Borrowers.

         B. The Borrowers, the Agent and the Lenders desire to amend the Credit
Agreement strictly in accordance with the terms hereof.


                                      TERMS
                                      -----

         In consideration of the premises and of the mutual agreements herein
contained, the parties agree as follows:

                                   ARTICLE I.
                                   AMENDMENTS
                                   ----------

         Upon fulfillment of the conditions set forth in Article III hereof, the
Credit Agreement shall be amended as follows:

                  1.1 Section 1.1 shall be amended by adding the following
language at the end of the definition of "EBITDA": "plus, the value of capital
stock of the Company contributed by the Company to employee benefit plans during
the period".

                  1.2 Section 1.1 shall be further amended by adding a new
definition in appropriate alphabetical order:

                  "Net Cash Proceeds" means, without duplication, in connection
         with any issuance or sale of any equity securities or debt securities
         or instruments or the incurrence of loans, the cash proceeds received
         from such issuance or incurrence, net of investment banking fees,
         reasonable and documented attorneys' fees, accountants' fees,
         underwriting discounts and commissions and other reasonable and
         customary fees and expenses actually incurred in connection
         therewith.

                  1.3 Section 2.6 shall be amended by adding a new Section
2.6.7 at the end thereof to read as follows:

                  2.6.7 In addition to all other payments required hereunder,
         the Borrowers shall prepay the Aggregate Total Outstandings and the
         Noteholder Obligations, on a pro rata basis

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         based on the Aggregate Total Outstandings under this Agreement and the
         aggregate outstanding amount of Noteholder Obligations under the Senior
         Note Agreement at the time of such prepayment, by an amount equal to
         (a) 100% of the Net Cash Proceeds of any Subordinated Indebtedness or
         similar obligation incurred at any time by any Borrower or any
         Guarantor, and (b) 100% of the Net Cash Proceeds of any capital
         contribution to the Company or any of its Subsidiaries (other than a
         capital contribution by the Company or any Subsidiary) or issuance of
         any Capital Stock of the Company (other than any issuance by the
         Company in connection with any employee stock purchase plans or any
         stock option plans). Such payments shall be applied to the Aggregate
         Total Outstandings on a pro rata basis between the U.S. Commitment and
         the Canadian Commitment, and such Commitments shall also be permanently
         reduced in connection with such prepayment; provided, that the amount
         of the reduction of the Commitments shall be calculated on a pro rata
         basis between the Aggregate Commitments (and not on Aggregate Total
         Outstandings) and the aggregate outstanding principal amount of the
         Noteholder Obligations.

                  1.4 Section 6.19 shall be amended by deleting Sections 6.19.1
and 6.19.2 and inserting the following in place thereof:

                  6.19.1 CONSOLIDATED FIXED CHARGE COVERAGE RATIO. The Company
         will not permit the Consolidated Fixed Charge Coverage Ratio of the
         Company and its Subsidiaries, determined as of the end of each of its
         fiscal quarters to be less than (i) 1.25 to 1.0 for the quarters ending
         September 30, 2000 and December 31, 2000, (ii) 1.40 to 1.0 for the
         quarter ending March 31, 2001 and (iii) 1.5 to 1.0 thereafter.

                  6.19.2 LEVERAGE RATIO. The Company will not permit the
         Consolidated Leverage Ratio of the Company and its Subsidiaries,
         determined as of the end of each of its fiscal quarters, to be greater
         than (i) 5.70 to 1.0 for the periods ending September 30, 2000 and
         December 31, 2000, (ii) 4.50 to 1.0 for the period ending March 31,
         2001, and (iii) 3.25 to 1.0 thereafter.

         1.5 The Pricing Schedule attached to the Credit Agreement shall be
amended by deleting the row entitled "Eurocurrency Rate" and inserting the
following in place thereof:

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------------
  APPLICABLE           LEVEL I       LEVEL II     LEVEL III     LEVEL IV     LEVEL V     LEVEL VI
  MARGIN                STATUS        STATUS        STATUS      STATUS       STATUS       STATUS
----------------------------------------------------------------------------------------------------
<S>                   <C>           <C>          <C>           <C>         <C>          <C>
  Eurocurrency Rate     1.20%          1.525%      1.875%         2.05%       2.25%        2.50%
----------------------------------------------------------------------------------------------------
</TABLE>



                                   ARTICLE 2.
                                REPRESENTATIONS
                                ---------------

         Each Borrower represents and warrants to the Agent and the Lenders
that:

         2.1 The execution, delivery and performance of this Amendment is within
its powers, has been duly authorized and is not in contravention with any law,
of the terms of its Articles of Incorporation or By-laws, or any undertaking to
which it is a party or by which it is bound.


                                      -2-
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         2.2 This Amendment is the legal, valid and binding obligation of such
Borrower enforceable against it in accordance with the terms hereof.

         2.3 After giving effect to the amendments herein contained, the
representations and warranties contained in Article IV of the Credit Agreement
are true on and as of the date hereof with the same force and effect as if made
on and as of the date hereof.

         2.4 No Default or Unmatured Default exists or has occurred and is
continuing on the date hereof.

                                   ARTICLE 3.
                           CONDITIONS OF EFFECTIVENESS
                           ---------------------------

         This Amendment shall not become effective until each of the following
has been satisfied:

         3.1 This Amendment shall be signed by the Borrowers and the Lenders.

         3.2 The Company and the Noteholders shall have executed an amendment to
the Senior Note Agreement, which amendment shall be satisfactory in form and
substance to the Required Lenders.


                                   ARTICLE 4.
                                 MISCELLANEOUS.
                                 --------------

         4.1 Notwithstanding Section 8.2 of the Credit Agreement, each of the
Lenders and the Borrowers agree that any amendment, modification or waiver of
the letter agreement dated on or about the date hereof between the Agent, on
behalf of the Lenders, and the Borrowers shall require only consent of the
Borrowers and the Required Lenders.

         4.2 References in the Credit Agreement or in any note, certificate,
instrument or other document to the "Credit Agreement" shall be deemed to be
references to the Credit Agreement as amended hereby and as further amended from
time to time.

         4.3 The Company agrees to pay and to save the Agent harmless for the
payment of all costs and expenses arising in connection with this Amendment,
including the reasonable fees of counsel to the Agent in connection with
preparing this Amendment and the related documents.

         4.4 Except as expressly amended hereby, each Borrower agrees that the
Credit Agreement, and all documents and agreements executed by such Borrower in
connection with the Credit Agreement in favor of the Agent or any Lender are
ratified and confirmed and shall remain in full force and effect and that it has
no set off, counterclaim or defense with respect to any of the foregoing. Terms
used but not defined herein shall have the respective meanings ascribed thereto
in the Credit Agreement.

         4.5 This Amendment may be signed upon any number of counterparts with
the same effect as if the signatures thereto and hereto were upon the same
instrument.

                                      -3-

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         IN WITNESS WHEREOF, the parties signing this Amendment have caused this
Amendment to be executed and delivered as of October 19, 2000.
                                                     --

                                        CORRPRO COMPANIES, INC.

                                        By: /s/ NEAL R. RESTIVO
                                           --------------------------------
                                        Its:  Executive VP and CFO
                                            -------------------------------


                                        CSI COATING SYSTEMS INC.

                                        By: /s/ NEAL R. RESTIVO
                                           --------------------------------
                                        Its: Vice President
                                            -------------------------------

                                        BANK ONE, MICHIGAN, as Agent and
                                        Individually as a Lender

                                        By: /s/ KELLY M. HAMRICK
                                           --------------------------------
                                        Its:  Vice President
                                            -------------------------------

                                        PNC BANK, NATIONAL ASSOCIATION

                                        By: /s/ Ronald L. Bovill
                                           --------------------------------
                                        Its: Sr. Vice President
                                            -------------------------------

                                        KEY BANK

                                        By: /s/ L. James Forshey
                                           --------------------------------
                                        Its: Vice President
                                            -------------------------------

                                      -4-


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                                        FIRST MERIT BANK

                                        By:  /s/ EDWARD YANNAYON
                                           --------------------------------
                                        Its: Vice President
                                            -------------------------------

                                        COMERICA BANK

                                        By: BRIAN MARSHALL
                                           --------------------------------
                                        Its: Vice President
                                            -------------------------------

                                        FIFTH THIRD BANK, NORTHEASTERN OHIO

                                        By:  /s/ David J. Williams
                                           --------------------------------
                                        Its: Vice President
                                            -------------------------------