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                                                                    EXHIBIT 4.12

                                    GUARANTY

      THIS GUARANTY is made and entered into as of January ____, 2005 (this
"Guaranty") by F.N.B. CORPORATION, a Florida corporation ("FNB") in favor of the
Holders (the "Holders") of certain Nonnegotiable Subordinated Term Notes,
Nonnegotiable Subordinated Daily Notes and Nonnegotiable Subordinated Special
Daily Notes (collectively, the "Securities") of FNB FINANCIAL SERVICES, LP, a
Delaware limited partnership (the "Company").

                               W I T N E S S E T H

      WHEREAS, it is a condition precedent to the Holders purchasing the
Securities that FNB executes this Guaranty; and

      WHEREAS, FNB will be receiving a direct or indirect corporate benefit as a
result of the issuance of the Securities and the application of the proceeds
thereof by the Company.

      NOW, THEREFORE, in consideration of the premises, and in order to induce
the Holders to purchase the Securities from the Company, FNB agrees as follows:

1.    GUARANTY.

      1.1 Obligations Guaranteed. FNB hereby irrevocably, absolutely and
unconditionally guarantees to the Holders and J.P. Morgan Trust Company,
National Association, as Trustee (the "Trustee") under the Indenture dated as of
January ____, 2005 by and among the Company, FNB as Guarantor and the Trustee
(the "Indenture"): (a) the full and prompt payment of the principal of all of
the Securities and of the interest thereon at the rate therein stipulated and
all other amounts owing to the Holders by the Company, when and as the same
shall become due and payable, whether by lapse of time, upon redemption or
prepayment, by extension or by acceleration or declaration, or otherwise, and
(b) the full and prompt performance and observance by the Company and Regency
Consumer Financial Services Inc., the Company's general partner (the "General
Partner"), of each and all of the covenants and agreements required to be
performed or observed by each of them under the terms of the Securities and the
Indenture, in each and every case irrespective of the validity, regularity or
enforcement of any of the Securities or the Indenture or any of the terms
thereof or of any other like circumstance or circumstances (all of the
obligations described in the foregoing clauses being referred to herein as the
"Guaranteed Obligations"). The guaranty of the Securities herein provided for is
a guaranty of the immediate and timely payment of the principal, interest and
all other amounts owing to the Holders under the Securities when and as the same
are due and payable and shall not be deemed to be a guaranty only of the
collectibility of such payments and that in consequence thereof each Holder may
sue FNB directly upon such principal, interest and other amounts becoming so due
and payable. All terms used in this Guaranty which are defined in the Indenture
and not otherwise defined herein shall have the meanings assigned to them in the
Indenture.

      1.2 Obligations Unconditional; Waivers.

      (a) The Guaranteed Obligations shall be absolute and unconditional and
shall remain in full force and effect until the entire principal, interest and
all other sums due to the Holders and the Trustee pursuant to the Securities or
the Indenture shall have been fully, finally and indefeasibly paid and such
Guaranteed Obligations shall not be affected, modified or impaired

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upon the happening from time to time of any event or condition, including
without limitation any of the following, whether or not with notice to or the
consent of FNB:

         (i)      the power or authority or the lack of power or authority of
                  the Company to issue the Securities or enter into the
                  Indenture and irrespective of the validity of the Securities
                  or the Indenture, or of any defense whatsoever that the
                  Company may or might have to the payment of the Securities or
                  any amounts payable under the Indenture (including, without
                  limitation, principal and interest) or to the performance or
                  observance of any of the provisions or conditions of the
                  Securities or the Indenture, or the existence or continuance
                  of the Company as a legal entity;

         (ii)     any failure to present the Securities for payment or to demand
                  payment thereof, or to give the Company or FNB notice of
                  dishonor for non-payment of the Securities, when and as the
                  same may become due and payable, or notice of any failure on
                  the part of the Company to do any act or thing or to perform
                  or to keep any covenant or agreement to be done, kept or
                  performed under the terms of the Securities or the Indenture;

         (iii)    the acceptance of any security or any guaranty, the advance of
                  additional money to the Company, any extension of the
                  obligation of the Securities or the Indenture, either
                  indefinitely or for any period of time, or any other
                  modification in the obligation of the Securities or the
                  Indenture or the Company thereon, or in connection therewith,
                  or any sale, release, substitution or exchange of any
                  security;

         (iv)     any act or failure to act with regard to the Securities or the
                  Indenture or anything which might vary the risk of FNB
                  (including, without limitation, any release or substitution of
                  any one or more of the endorsers or guarantors of the
                  Guaranteed Obligations);

         (v)      any failure or omission on the part of any Holder or the
                  Trustee to first enforce any right against the Company,
                  provided that nothing in this Section shall entitle any Holder
                  or the Trustee to recover twice any sums claimed pursuant to
                  this Guaranty;

         (vi)     the extension of the time for payment of any principal of, or
                  interest on, any Security owing or payable on such Security;

         (vii)    any failure, omission, delay or lack on the part of the
                  Holders or the Trustee to enforce, assert or exercise any
                  right, power or remedy conferred on the Holders or the Trustee
                  or any other act or acts on the part of the Holders or the
                  Trustee;

         (viii)   the voluntary or involuntary liquidation, dissolution, sale or
                  other disposition of all or substantially all the assets,
                  marshaling of assets and liabilities, receivership,
                  insolvency, bankruptcy, assignment for the benefit of
                  creditors, reorganization or arrangement under bankruptcy or
                  similar laws, composition with creditors or readjustment of,
                  or other similar procedures affecting the Company or FNB or
                  any of the assets of either of them (it being understood that
                  the obligations of FNB under this Guaranty shall continue to
                  be effective or be reinstated, as the case may be, if at any
                  time any payment made with respect to the Securities or

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                  the Indenture is rescinded or must otherwise be restored or
                  returned by any Holder or the Trustee upon the insolvency,
                  bankruptcy or reorganization of the Company or FNB, all as
                  though such payment had not been made);

         (ix)     any event or action that would, in the absence of this clause,
                  result in the release or discharge by operation of law of FNB
                  from the performance or observance of any obligation, covenant
                  or agreement contained in this Guaranty;

         (x)      the invalidity or unenforceability of the obligations of FNB
                  under this Guaranty, the absence of any action to enforce such
                  obligations of FNB, any waiver or consent by FNB with respect
                  to any of the provisions hereof or any other circumstances
                  which might otherwise constitute a discharge or defense by
                  FNB, including, without limitation, any failure or delay in
                  the enforcement of the obligations of FNB with respect to this
                  Guaranty or of notice thereof; or any suit or other action
                  brought by any shareholder or creditor of, or by, FNB or any
                  other person, for any reason, including, without limitation,
                  any suit or action in any way attacking or involving any
                  issue, matter or thing in respect of the Securities or any
                  other agreement;

         (xi)     the impossibility or illegality of performance on the part of
                  the Company of its obligations under the Securities, the
                  Indenture or any other instruments;

         (xii)    in respect of the Company, any change of circumstances,
                  whether or not foreseen or foreseeable, whether or not
                  imputable to the Company, or other impossibility of
                  performance through fire, explosion, accident, labor
                  disturbance, floods droughts, embargoes, wars (whether or not
                  declared), civil commotions, acts of God or the public enemy,
                  delays or failure of suppliers or carriers, inability to
                  obtain materials, action of any regulatory body or agency,
                  change of law or any other causes affecting performance, or
                  other force majeure, whether or not beyond the control of the
                  Company and whether or not of the kind hereinbefore specified;

         (xiii)   any attachment, claim, demand, charge, lien, order, process,
                  encumbrance or any other happening or event or reason, similar
                  or dissimilar to the foregoing, or any withholding or
                  diminution at the source, by reason of any taxes, assessments,
                  expenses, indebtedness, obligations or liabilities of any
                  character, foreseen or unforeseen, and whether or not valid,
                  incurred by or against any person, or any claims, demands,
                  charges or liens of any nature, foreseen or unforeseen,
                  incurred by any person, or against any sums payable under the
                  Securities or the Indenture, so that such sums would be
                  rendered inadequate or would be unavailable to make the
                  payments herein provided;

         (xiv)    the failure of FNB to receive any benefit or consideration
                  from or as a result of its execution, delivery and performance
                  of this Guaranty;

         (xv)     any sale, exchange, release or surrender of any property at
                  any time pledged or granted as security in respect of the
                  Guaranteed Obligations; or

         (xvi)    any other circumstance which might otherwise constitute a
                  defense available to, or a discharge of, FNB in respect of the
                  obligations of FNB under this Guaranty.

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PROVIDED that the specific enumeration of the above-mentioned acts, failures or
omissions shall not be deemed to exclude any other acts, failures or omissions,
though not specifically mentioned above, it being the purpose and intent of this
Guaranty that the obligations of FNB hereunder shall be absolute and
unconditional to the extent herein specified and shall not be discharged,
impaired or varied except by the full, final and indefeasible payment to the
Holders of the principal of, interest on, and any other amounts due in respect
of the Securities or to the Trustee under the Indenture, and then only to the
extent of such payments. Without limiting any of the other terms or provisions
hereof, it is understood and agreed that in order to hold FNB liable hereunder,
there shall be no obligation on the part of any holder of any Security or the
Trustee to resort, in any manner or form, for payment, to the Company, to any
other person or to the properties or estates of any of the foregoing. All rights
of the Holders pursuant thereto, and of the Holders and Trustee pursuant to the
Indenture and under this Guaranty shall be considered to be transferred or
assigned upon the valid transfer of such Security on the books of the Company.
Without limiting the foregoing, it is understood that repeated and successive
demands may be made and recoveries may be had hereunder as and when, from time
to time, the Company shall default under the terms of the Securities or the
Indenture and that notwithstanding recovery hereunder for or in respect of any
given default, this Guaranty shall remain in full force and effect and shall
apply to each and every subsequent default.

      (b) Except as otherwise provided in this Guaranty, to the fullest extent
permitted by law, FNB does hereby expressly waive:

      (i)   all of the matters specified in clause (a) of this Section 1.2 and
            any notices in respect thereof;

      (ii)  notice of any purchase or acceptance of the Securities or the
            creation, existence or acquisition of any of the Guaranteed
            Obligations, subject to FNB's right to make inquiry of each Holder
            and the Trustee to ascertain the amount of the Guaranteed
            Obligations at any reasonable time;

      (iii) notice of the amount of the Guaranteed Obligations, subject to FNB's
            right to make inquiry of each Holder and the Trustee to ascertain
            the amount of the Guaranteed Obligations at any reasonable time; and

      (iv)  any stay (except in connection with a pending appeal), valuation,
            appraisal, redemption or extension law now or at any time hereafter
            in force that, but for this waiver, might be applicable to any sale
            of property of FNB made under any judgment, order or decree based on
            this Guaranty, and FNB covenants that it will not at any time insist
            upon or plead, or in any manner claim or take the benefit or
            advantage of any such law.

      (c) Each of the rights and remedies granted under this Guaranty to each
Holder and the Trustee may be exercised by such Holder and the Trustee without
notice to, or the consent of or any other action by, any other Holder or the
Trustee, subject to the terms of the Indenture. Each Holder and the Trustee may
proceed to protect and enforce this Guaranty by suit or suits or proceedings in
equity, at law or in bankruptcy, and whether for the specific performance of any
covenant or agreement contained herein or in execution or aid of any power
herein granted, subject to the terms of the Indenture; or for the recovery of
judgment for the obligations hereby guaranteed or for the enforcement of any
other proper, legal or equitable remedy available under applicable law, subject
to the terms of the Indenture.

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      (d) If any Holder or the Trustee shall have instituted any proceeding to
enforce any right or remedy under this Guaranty or under any Security held by
such Holder or under the Indenture and such proceeding shall have been
discontinued or abandoned for any reason, or shall have been determined
adversely to such holder, then and in every such case each such Holder or the
Trustee and the Company shall, except as may be limited or affected by any
determination in such proceeding, be restored severally and respectively to its
respective former position hereunder and thereunder, and thereafter the rights
and remedies of such Holders or the Trustee shall continue as though no such
proceeding had been instituted.

      (e) The obligations of FNB under this Guaranty shall not be discharged nor
shall FNB's liability be affected by any reduction occurring in, or any
arrangement being made relating to any of the Company's liabilities to one or
more Holders or the Trustee as a result of any arrangement or composition made
pursuant to any provisions of any applicable bankruptcy or insolvency laws or
any analogous provision or made pursuant to any proceedings or actions
whatsoever and whether or not following the appointment of any administrator,
administrative receiver, trustee, liquidator, receiver or examiner or any
similar officer to the Company or over all or a substantial part of the Company,
and FNB hereby agrees that the amount recoverable by the Holders or the Trustee
from FNB hereunder will be and will continue to be the full amount which would
have been recoverable by the Holders or the Trustee from the Company in respect
of the Company's liabilities had no such arrangement or composition as aforesaid
been entered into.

2. COLLECTION EXPENSES. In the event that FNB shall be required to make any
payment to any Holder or the Trustee pursuant to the provisions of this
Guaranty, FNB shall, in addition to such payment, pay to such Holder or the
Trustee such further amount as shall be sufficient to cover the reasonable costs
and expenses of collection of the Holder or the Trustee, including, without
limitation, the reasonable costs and expenses of attorneys or financial advisors
incurred in connection with the evaluation and enforcement of any rights
hereunder and any reasonable expenses or liabilities incurred by any Holder or
the Trustee hereunder. FNB's obligations under this Section 2 shall survive the
payment of the Securities, provided that FNB shall not be required to pay any
further amounts, costs, expenses or liabilities than have otherwise been paid
pursuant to the terms of this Guaranty.

3. SUBROGATION. To the extent of any payments made under this Guaranty, FNB
shall be subrogated to the rights of the Holder or the Trustee receiving such
payments, but FNB covenants and agrees that such right of subrogation shall be
subordinate in right of payment to the rights of any Holders or the Trustee for
which full payment has not been made or provided for and, to that end, FNB
agrees not to claim or enforce any such right of subrogation or any right of
setoff or any other right which may arise on account of any payment made by FNB
in accordance with the provisions of this Guaranty unless and until all of the
Securities and all other sums due or payable under this Guaranty have been fully
paid and discharged.

4. PREFERENCE; MARSHALING.

      (a) FNB agrees that to the extent the Company makes any payment on the
Securities or to the Trustee under the Indenture, which payment or any part
thereof is subsequently invalidated, voided, declared to be fraudulent or
preferential, set aside, or is required to be repaid to a trustee, receiver or
any other person under any bankruptcy code, common law or equitable cause, then
and to the extent of such payment, the obligation or the part thereof intended
to be satisfied shall be revived and continued in full force and effect with
respect to FNB's obligations hereunder, as if said payment had not been made.
The liability of FNB hereunder shall not be reduced or discharged, in whole or
in part, by any payment to any Holder or to the Trustee under

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the Indenture from any source that is thereafter paid, returned or refunded in
whole or in part by reason of the assertion of a claim of any kind relating
thereto, including, but not limited to, any claim for breach of contract, breach
of warranty, preference, illegality, invalidity or fraud asserted by any account
debtor or by any other person.

      (b) None of the Holders or the Trustee shall be under any obligation (i)
to marshal any assets in favor of FNB or in payment of any or all of the
liabilities of the Company under or in respect of the Securities or the
obligations of FNB hereunder or (ii) to pursue any other remedy that FNB may or
may not be able to pursue itself and that may lighten FNB's burden, any right to
which FNB hereby expressly waives.

      5. SUBORDINATION. The indebtedness evidenced by the Securities is
subordinate to the prior payment when due of the principal of and interest on
all Senior Indebtedness (as such term is defined below). Upon maturity of any
Senior Indebtedness, payment in full must be made on such Senior Indebtedness
before any payment is made on or in respect of the Securities or this Guaranty.
During the continuance of any default in payment of principal of or interest or
sinking fund on any Senior Indebtedness, or any other event of default with
respect to Senior Indebtedness pursuant to which the holders thereof have
accelerated the maturity thereof, no direct or indirect payment may be made or
agreed to be made by the Company or FNB on or in respect of the Securities or
this Guaranty. Upon any distribution of assets of the Company or FNB in any
dissolution, winding up, liquidation or reorganization, payment of the principal
of and interest on the Securities or this Guaranty will be subordinated, to the
extent and in the manner set forth in the Indenture, to the prior payment in
full of all Senior Indebtedness. The Indenture does not limit the Company's or
FNB's ability to increase the amount of Senior Indebtedness or to incur any
additional indebtedness in the future that may affect the Company's or FNB's
ability to make payments under the Securities or this Guaranty. Except as
described above, the obligation of the Company or FNB to make payment of
principal or interest on the Securities or this Guaranty will not be affected.
By reason of such subordination, in the event of a distribution of assets upon
insolvency, certain general creditors of the Company and FNB may recover more,
ratably, than Holders of the Securities.

      "Senior Indebtedness" means Indebtedness of the Company or FNB outstanding
at any time, other than Indebtedness of the Company or FNB to each other or to a
Subsidiary for money borrowed or advanced from the other or from any such
Subsidiary or Indebtedness which by its terms is not superior in right of
payment to the Securities, provided, however, that for purposes of clarity, the
obligations of FNB under this Guaranty with respect to the Indebtedness
represented by the Securities and this Guaranty shall be pari passu with the
Indebtedness of FNB under that certain Indenture, dated as of May 15, 1992, as
amended, between FNB and J.P. Morgan Trust Company, National Association,
successor trustee to Northern Central Bank, as trustee. "Indebtedness" means (1)
any debt of the Company or FNB (i) for borrowed money or (ii) evidenced by a
note, debenture or similar instrument (including a purchase money obligation)
given in connection with the acquisition of any property or assets, including
securities; (2) any debt of others described in the preceding clause (1) which
the Company or FNB has guaranteed or for which it is otherwise liable; and (3)
any amendment, renewal, extension or refunding of any such debt.

6. ENTIRE AGREEMENT; AMENDMENTS; WAIVERS. FNB hereby agrees that this instrument
contains the entire agreement of FNB regarding its subject matter, and that
there is and can be no other oral or written agreement or understanding whereby
the provisions of this instrument have been or can be terminated, affected,
varied, waived, amended or modified in any manner, unless the same be set forth
and consented to in writing by FNB and a Holder or the

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Trustee. Any consent given pursuant to this Section 6 by a Holder which has (i)
transferred or agreed to transfer all or a portion of its Securities to the
Company, FNB or any subsidiary and (ii) provided such consent as a condition to
such transfer, shall be valid and binding only upon such holder. Any amendment
or waiver which becomes effective only with such consent (and the consents of
all other Holders which were acquired under the same or similar conditions)
shall be valid and binding only upon such Holder(s).

7. SUCCESSORS AND ASSIGNS. In respect of the obligations of the Company under
the Securities and the Indenture, this Guaranty shall be binding upon and inure
to the benefit of the Holders and the Trustee (and for this purpose FNB may
treat the person in whose name any Security is registered in the register
maintained by the Company as the owner and holder of such Security for all
purposes whatsoever and FNB shall not be affected by notice to the contrary). In
respect of all other obligations of the Company guaranteed by this Guaranty,
this Guaranty shall be binding upon and inure to the benefit of the respective
successors and assigns of FNB and of any Holder and the Trustee. This Guaranty
shall without further consent of FNB, pass to, and may be relied upon and
enforced by, any successor or assignee of any Holder and any transferee or
subsequent registered holder of any Security and the Trustee.

8. NOTICES. All notices and communications provided for hereunder shall be in
writing and sent (a) by telecopy if the sender on the same day sends a
confirming copy of such notice by a recognized overnight delivery service
(charges prepaid), or (b) by a recognized overnight delivery service (with
charges prepaid). Any such notice must be sent: (x) if to a Holder, at such
other address as such Holder shall have specified to the Company in writing, (y)
if to the Trustee, to such Trustee at One Oxford Centre, Suite 1100, 301 Grant
Street, Pittsburgh, Pennsylvania 15219, Attn: Institutional Trust Services, or
at such other address as the Trustee shall have specified to FNB and the holder
of each Security in writing, or (z) if to FNB, to FNB at One FNB Boulevard,
Hermitage, Pennsylvania 16148, Attn: Legal Department, or at such other address
as FNB shall have specified to the holder of each Security in writing. Notices
under this Section 7 will be deemed given only when actually received.

9. GOVERNING LAW. This Guaranty shall be construed and enforced in accordance
with, and the rights of the parties shall be governed by, the law of the State
of Delaware excluding its choice of law principles that would require the
application of the laws of another jurisdiction.

10. NO WAIVER. No delay on the part of any Holder or the Trustee in exercising
any rights hereunder or failure to exercise the same shall operate as a waiver
of such rights; no notice to or demand on FNB shall be deemed to be a waiver of
the obligation of FNB or of the rights of any Holder or the Trustee to take
further action without notice or demand as provided herein.

11. HEADINGS. The descriptive headings of the several Sections of this Guaranty
are inserted for convenience only and do not constitute a part of this Guaranty.

12. SEVERABILITY. Any provision of this Guaranty that is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall (to the full extent permitted by law) not invalidate or
render unenforceable such provision in any other jurisdiction.

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      IN WITNESS WHEREOF, FNB has caused this Guaranty to be executed as of the
date first above written.

                                            F.N.B. CORPORATION,
                                              a Florida corporation

                                            By: ________________________________
                                            Name: ______________________________
                                            Title: _____________________________

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