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                        COMMONWEALTH GROUP HOLDINGS, LLC


                                                                   Exhibit 10.18

                                                                   March 5, 2003

Phillip S. Dingle
Chairman & Chief Executive Officer
PlanVista Corporation
4010 Boy Scout Boulevard
Tampa, FL  33607

Dear Phil:

     The purpose of this letter is to confirm the engagement of Commonwealth
Group Holdings, LLC ("Commonwealth") by PlanVista Corporation (the "Company") to
act as the Company's non-exclusive financial advisor to provide financial
advisory services and other investment banking services to the Company as set
forth below.

     Section 1. Services. During the term of this Agreement, Commonwealth shall
provide the Company with the services described below and such other regular and
customary financial consulting advice as is reasonably requested by the Company,
provided that Commonwealth shall not be required to undertake duties not
reasonably within the scope of this Agreement. It is understood and acknowledged
by the parties that the value of Commonwealth's services is not readily
quantifiable, and that although Commonwealth shall be obligated to render such
services contemplated by this Agreement upon the reasonable request of the
Company, in good faith, Commonwealth shall not be obligated to spend any
specific amount of time in so doing. Commonwealth will perform the following
financial advisory and investment banking services:

     (a)  Commonwealth will familiarize itself to the extent it deems
          appropriate and feasible with the business, operations, properties,
          financial condition, prospects, and capitalization of the Company, it
          being understood that Commonwealth shall, in the course of such
          familiarization, rely entirely upon publicly available information and
          such other information as may be supplied by the Company, without
          independent investigation; and

     (b)  Commonwealth will generally advise the Company on its existing capital
          structure and assist the Company in restructuring certain of its
          existing capital structure including, without limitation, the
          HealthPlan Holdings make-whole provisions, and the Centra convertible
          subordinated debt; and

     (c)  Commonwealth will generally advise the Company on its existing long
          and short term debt and certain of its other liabilities and assist
          the Company in restructuring such debt (collectively with the activiti
          es referred to in (b) above, hereinafter referred to as the
          "Restructuring Activities"). The foregoing notwithstanding,
          Restructuring Activities shall not include the restructuring of any
          debts or equity held by Commonwealth or any affiliate of Commonwealth.
          As used in this Agreement, the term affiliate shall have the meaning
          ascribed thereto under Rule 13d of the Securities Exchange Commission;
          and

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     (d)  Commonwealth will introduce the Company to investment banks or other
          sources of capital in order to assist the Company in raising between
          $20 million and $50 million of new senior debt and/or other debt or
          equity financing (the "Financing Activities"); and

     (e)  Commonwealth will seek to introduce the Company to new potential
          business partners and customers as well as generally advise the
          Company on its business development efforts; and

     (f)  Commonwealth will devote at least one of its senior managers to assist
          the Company's management in evaluating all aspects of the Company's
          business; and

     (g)  Commonwealth will render such other financial advisory and investment
          banking services as may from time to time be agreed upon by
          Commonwealth and the Company.

In connection with our activities on the Company's behalf, subject to any
confidentiality obligations the Company owes to third parties, the Company will
furnish us with all information (the "Information") which we may reasonably
request and is reasonably acceptable to the Company and will provide us
reasonable access to the Company's officers, directors, accountants and counsel.
The Company represents and warrants that to the best of its knowledge the
information will be true, accurate and complete and will not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein not misleading. The
Company further represents and warrants that any projections provided to us or
contained in any materials prepared by the Company will have been prepared in
good faith and will be based upon assumptions which, in light of the
circumstances under which they are made, are reasonable. The Company
acknowledges and agrees that, in rendering our services hereunder, we will be
using and relying on the Information (and information available from public
sources and other sources which we deem to be reliable) without independent
verification thereof and without independent appraisal of any of the Company's
assets. We do not assume responsibility for the accuracy or the completeness of
the Information or any other information regarding the Company. Unless it
obtains the prior written consent of the Company, Commonwealth shall not
disclose to any person any non-public information provided by the Company to
Commonwealth. Commonwealth's engagement is non-exclusive and nothing contained
herein shall in any way be deemed to prohibit or restrict the ability of the
Company to retain and pay other investment bankers including but not limited to
retaining them to do any of the services which Commonwealth has been retained to
do. Commonwealth shall not be entitled to a fee on any matter which is
negotiated, introduced or initiated by such other investment bankers.

     Section 2. Fees. The Company shall pay to Commonwealth for its services
hereunder the following fees:

     (a)  On account of the ongoing nature of Commonwealth's services hereunder
          including, without limitation, assisting and advising management and
          the Board of Directors on all financial and general business matters
          and other general management services, a monthly cash fee equal to
          $15,000 per month for a period of 24 months thereafter (unless
          terminated in writing by the Company after 12 months upon 60 days
          prior written notice); and

     (b)  On account of the assistance provided by Commonwealth in effectuating
          the restructuring of the Company's balance sheet, upon the completion
          of the Restructuring Activities, a fee equal to 3% as follows:

          a.   A cash fee equal to 3% of the face value of any debt owned by
               persons other than Commonwealth and its affiliates which is
               repaid in cash plus 3% of the liquidation

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               value of any equity owned by persons other than Commonwealth and
               its affiliates which is redeemed in cash; plus

          b.   Equity equal to 3% of any equity issued in connection with any
               conversion or exchange of any outstanding debt or equity of the
               Company owned by persons other than Commonwealth and its
               affiliates. To the extent that, under covenants, agreements or
               law applicable at the time such fee is to be paid, the Company is
               prohibited from making such payment to Commonwealth in equity,
               such payment shall be made to Commonwealth in cash. In the event
               that cash is to be paid to Commonwealth pursuant to this Section
               2 (b)b, the value of any publicly traded equity issued in
               connection with any conversion or exchange of debt or equity
               shall be the average closing sales price of such issued equity
               over the 20 trading days immediately prior to closing of such
               conversion or exchange.

     Section 3. Additional Services. In addition to the above:

     (a)  If Commonwealth participates as an underwriter, placement agent or
finder, in the sale or distribution of securities by the Company to the public
or in a private transaction (an "Offering"), Commonwealth shall receive, as
compensation for services rendered, such fees as shall be negotiated between the
Company and Commonwealth at such time. In the event Commonwealth originates a
senior secured asset based lending facility or other similar bank financing for
the Company, the Company shall pay to Commonwealth a cash fee equal to 2% of the
maximum amount of such facility or loan. To the extent that any fee payable
under Section 2(b)a is as a direct result of any financing pursuant to this
Section 3(a), then the Company shall not owe any fee under this section for the
portion of such financing used to effectuate the Restructuring.

     (b)  If, during the term of this Agreement, the Company completes any M&A
Transaction (as defined below), or if during the 12 month period following the
term of this Agreement the Company completes an M&A Transaction with any party
who was either identified by Commonwealth during the term of this Agreement or
who held any discussions or negotiations with the Company after having been
introduced to the Company by Commonwealth during the term of this Agreement
relating to an M&A Transaction, then the Company shall pay to Commonwealth a
cash fee equal to 1.5% of the Total Consideration (as defined below) paid in
such transaction. For purposes hereof, an M&A Transaction shall include (i) the
sale of all or a substantial part of the Company to another corporation or other
business entity, whether such transaction is in the form of a merger, sale of
assets or equity securities, or joint venture or other similar business
combination, or (ii) the acquisition of all or a substantial part of another
corporation or other business entity, whether such transaction is in the form of
a merger, purchase of assets or equity securities, or joint venture or other
similar business combination. In the event that Commonwealth or the Company
(acting with the written consent of Commonwealth, which shall not be withheld
unreasonably) engages any other advisor, finder or investment bank to assist it
in any such M&A Transaction, any fee payable to such person or entity shall be
payable from the 1.5% fee payable to Commonwealth pursuant to this section. In
the event that Commonwealth or its affiliates makes a proposal to engage in an
M&A Transaction with the Company, Commonwealth shall not serve as advisor to the
Company with respect to such proposed M&A Transaction.

          For purposes of this Agreement, "Total Consideration" shall mean the
total value of all cash, securities, or other property either paid at the
closing of an M&A Transaction, or paid in the future if such M&A Transaction is
consummated in one or more steps, to or by the Company or its shareholders or to
be paid in the future to or by them with respect to such M&A Transaction (other
than payments of interest or dividends) in respect of (i) the assets of the
company being acquired or sold, (ii) the capital stock of the company being
acquired or sold (and any securities convertible into options, warrants or

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     other rights to acquire such capital stock) and (iii) the assumption,
directly or indirectly (by operation of law or otherwise), of any long-term
liabilities of the Company or repayment of indebtedness, including without
limitation, indebtedness secured by the assets of the company being acquired or
sold.

          All fees to be paid pursuant to this Section 3, except as otherwise
agreed in writing, are due and payable to Commonwealth in cash at the closing or
closings of any transaction provided that any fees which are payable on future
payments shall not be due until such future payments are made. In the event that
this Agreement shall not be renewed, or if this Agreement is terminated for any
reason, then notwithstanding any such non-renewal or termination, Commonwealth
shall be entitled to receive the full fee provided for hereunder for any
transaction for which the discussions or introductions were initiated during the
term of this Agreement and for which Commonwealth would otherwise be entitled to
a fee hereunder. If the Company pays a fee to Commonwealth under Section 2, it
shall not be required to pay another fee under Section 3 on the same or related
transaction. In addition, any fees paid by the Company to Commonwealth pursuant
to Section 2(a) prior to any transaction that results in a fee being owed to
Commonwealth pursuant to Section 2(b) or Section 3 shall be offset against any
amount owed by the Company to Commonwealth pursuant to Section 2(b) or Section
3.

     Section 4. Expenses. In addition to the compensation described in Section 2
and 3 above, the Company agrees to promptly reimburse us, upon request from time
to time, not more than monthly, for all out-of-pocket expenses incurred
(including, without limitation, all travel and lodging expenses, and reasonable
fees and disbursements of any counsel, consultants and advisors retained by us
with the Company's consent) in connection with our services pursuant to this
Agreement; provided, however, that (i) unless otherwise consented to in writing
by the Company in advance such expenses with respect to such services (other
than those related to the Financing Activities and the Restructuring Activities)
shall not exceed $20,000 in the aggregate, and shall not exceed $100,000 in the
aggregate with respect to the Restructuring and Financing Activities and (ii)
the Company need only reimburse expenses that are appropriately documented, in
conformity with Company travel policies and in compliance with applicable
Internal Revenue Service regulations

     Section 5. Successors and Assigns. The benefits of this Agreement shall
inure to the respective successors and assigns of the parties hereto and of the
indemnified parties hereunder and their successors and assigns and
representatives, and the obligations and liabilities assumed in this agreement
by the parties hereto shall be binding upon their respective successors and
assigns; provided, that the rights and obligations of either party under this
agreement may not be assigned without the prior written consent of the other
party hereto and any other purported assignment shall be null and void.

     Section 6. Indemnification. The Company agrees to indemnify and hold
harmless Commonwealth, its employees, agents, representatives and controlling
persons from and against any and all losses, claims, damages, liabilities,
suits, actions, proceedings, costs and expenses (collectively, "Damages"),
including, without limitation, reasonable attorney fees and expenses, as and
when incurred, if such Damages were directly or indirectly caused by, relating
to, based upon or arising out of the rendering by Commonwealth of services
pursuant to this Agreement, so long as Commonwealth shall not have engaged in
intentional or willful misconduct or gross negligence in connection with the
services provided which form the basis of the claim for indemnification. This
paragraph shall survive the termination of this Agreement.

     Section 7. Miscellaneous.

     (a) The validity and interpretation of this Agreement shall be governed by
the law of the State of Delaware applicable to agreements made and to be fully
performed therein. Commonwealth and the Company will attempt to settle any claim
or controversy arising out of this Agreement through

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consultation and negotiation in good faith and a spirit of mutual cooperation.
If those attempts fail, then the dispute will be mediated by a mutually
acceptable mediator to be chosen by Commonwealth and the Company within 15 days
after written notice from either party demanding mediation. Neither party may
unreasonably withhold consent to the selection of a mediator, and the parties
will share the costs of the mediation equally. Any dispute which the parties
cannot resolve through negotiation or mediation within six months of the date of
the initial demand for it by one of the parties may then be submitted to binding
arbitration under the rules of the American Arbitration Association for
resolution. The use of mediation will not be construed under the doctrine of
latches, waiver or estoppel to affect adversely the rights of either party.
Nothing in this paragraph will prevent either party from resorting to judicial
proceedings if (a) good faith efforts to resolve the dispute under these
procedures have been unsuccessful or (b) interim relief from a court is
necessary to prevent serious and irreparable injury.

     (b) The Company expressly acknowledges that all opinions and advice
(written or oral) given by Commonwealth to the Company in connection with
Commonwealth's engagement are intended solely for the sole benefit and use of
the Company's board of directors and executive officers, and may not be used for
any other purpose or quoted or cited in any documents or public filings without
the express written consent of Commonwealth, which may be withheld for any
reason. The foregoing notwithstanding, the Company shall be entitled to disclose
the existence and terms of this relationship and this Agreement and
Commonwealth's actions in connection therewith as required by law or by
applicable regulations of the Securities and Exchange Commission.

     (c) The Company is a sophisticated business enterprise that has retained
Commonwealth for the limited purposes set forth in this Agreement, and the
parties acknowledge and agree that their respective rights and obligations are
contractual in nature. Each party disclaims an intention to impose fiduciary
obligations on the other by virtue of the engagement contemplated by the
Agreement.

     (d) The Company represents and warrants to Commonwealth that Commonwealth's
engagement hereunder has been duly authorized and approved by the Board of
Directors of the Company and this letter agreement has been duly executed and
delivered by the Company and constitutes a legal, valid and binding obligation
of the Company.

     (e) Commonwealth represents and warrants to the Company that Commonwealth's
engagement hereunder has been duly authorized and approved by the Board of
Directors of Commonwealth and this letter agreement has been duly executed and
delivered by Commonwealth and constitutes a legal, valid and binding obligation
of Commonwealth.

     Section 8. Termination. The Agreement shall remain in effect until
terminated by either party. Either party may terminate this agreement at any
time after 12 months after execution of the Agreement, upon 60 days prior
written notice.

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     Please sign this letter at the place indicated below, whereupon it will
constitute our mutually binding agreement with respect to the matters contained
herein.

                                            Very truly yours,

                                            COMMONWEALTH GROUP HOLDINGS, LLC

                                            By: /s/ Carl Kleidman
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                                                Name:  Carl Kleidman
                                                Title: Managing Director

Agreed to and accepted:

PLANVISTA CORPORATION



By: /s/ Phillip S. Dingle
    -------------------------
    Name:  Phillip S. Dingle
    Title: Chairman and CEO

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