GUARANTY AGREEMENT


                THIS GUARANTY AGREEMENT (this "Guaranty"),  dated as of June 11,
1997, made by ARIZONA REPAIR SERVICES, INC., an Arizona corporation ("ARS"), and
ENHANCED SYSTEMS,  INC., an Arizona corporation ("ESI", ARS and ESI are referred
to herein  individually as a "Guarantor" and collectively as the  "Guarantors"),
in favor of GENERAL  ELECTRIC CAPITAL  CORPORATION,  a New York corporation (the
"Guaranteed Party").

                              W I T N E S S E T H:
                              - - - - - - - - - -

                WHEREAS,   Vodavi  Communications   Systems,  Inc.,  an  Arizona
corporation  formerly known as V Technology  Acquisition Corp. (the "Borrower"),
and  the  Guaranteed  Party  are  parties  to an  Amended  and  Restated  Credit
Agreement,  dated as of April 11, 1994, as amended and restated  effective as of
June 11, 1997 (as the same may hereafter be amended,  restated,  supplemented or
otherwise modified from time to time, the "Credit Agreement";  the terms defined
therein and not otherwise  defined herein being used herein as therein defined),
pursuant to which the Guaranteed  Party has committed to make a Revolving Credit
Loan available to the Borrower; and

                WHEREAS,  the Borrower and the  Guarantors  share an identity of
interests as members of a  consolidated  group of  companies  engaged in similar
businesses,  and the  making  of the  Revolving  Credit  Loan  available  to the
Borrower will facilitate  expansion and enhance the overall  financial  strength
and stability of the Borrower's corporate group, including the Guarantors; and

                WHEREAS,  it is a condition  precedent to the Guaranteed Party's
obligations  to make the  Revolving  Credit  Loan  available  under  the  Credit
Agreement  that the  Guarantors  execute  and  deliver  this  Guaranty,  and the
Guarantors desire to execute and deliver this Guaranty to satisfy such condition
precedent.

                  NOW, THEREFORE,  in consideration of the premises and in order
to induce the Guaranteed Party to make the Revolving Credit Loan available under
the Credit Agreement, each Guarantor hereby agrees as follows:

                1.  Guaranty  of   Obligations.   (a)  Each   Guarantor   hereby
absolutely,  unconditionally and irrevocably  guarantees to the Guaranteed Party
the prompt payment when due,  whether at stated  maturity,  by  acceleration  or
otherwise, of the Revolving Credit Loan and all other Obligations (as defined in
the Credit Agreement, and including all renewals, extensions, modifications, and
refinancings  thereof)  now  or  hereafter  existing,   whether  for  principal,
interest,  fees, expenses or otherwise,  and all expenses (including  reasonable
attorney's fees and expenses)  incurred by the Guaranteed Party in enforcing any
of its rights under the Credit  Agreement and the other Loan  Documents  (all of
the foregoing, collectively, the "Guaranteed Obligations"). Any and all payments
made by any  Guarantor  hereunder  shall be made free and  clear of and  without
deduction for any set-off, counterclaim, or
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withholdings so that, in each case, the Guaranteed  Party shall receive the full
amount  that it would  otherwise  be  entitled  to receive  with  respect to the
Guaranteed Obligations.

                (b) Each Guarantor acknowledges and agrees that this Guaranty is
a guaranty  of payment  and not of  collection  and that the  liability  of such
Guarantor  under this  Guaranty  shall be immediate and primary and shall not be
contingent  upon the  exercise or  enforcement  by the  Guaranteed  Party of any
remedies  the  Guaranteed  Party  may have  against  the  Borrower  or any other
Guarantor any other person or the  enforcement of any lien or  realization  upon
any  collateral  the  Guaranteed  Party may at any time  possess  for any of the
Guaranteed Obligations.

                2. Maximum Liability;  Contribution.  (a) It is the intention of
each  of  the  Guarantors  and  the  Guaranteed   Party  that  each  Guarantor's
obligations hereunder shall be in, but not in excess of, the maximum amount (the
"Maximum Guaranty Liability") permitted by applicable federal bankruptcy,  state
insolvency,  fraudulent  conveyance  or  transfer or similar  laws  ("Applicable
Law"). To that end, but only to the extent such  obligations  would otherwise be
subject to avoidance under Applicable Law if any Guarantor is not deemed to have
received valuable  consideration,  fair value or reasonably equivalent value for
its obligations  hereunder,  each Guarantor's  respective  obligations hereunder
shall be reduced to that amount which,  after giving effect  thereto,  would not
render such Guarantor insolvent, or leave such Guarantor with unreasonably small
capital to conduct its business,  or cause such Guarantor to have incurred debts
(or  intended to have  incurred  debts)  beyond its ability to pay such debts as
they mature, at the time such obligations are deemed to have been incurred under
Applicable Law. As used herein,  the terms "insolvent" and  "unreasonably  small
capital" shall likewise be determined in accordance  with  Applicable  Law. This
Section  is  intended  solely to  preserve  the rights of the  Guaranteed  Party
hereunder to the maximum  extent  permitted by  Applicable  Law, and neither the
Guarantors  nor any  other  Persons  shall  have any right or claim  under  this
Section  that would not  otherwise  be  available  under  Applicable  Law.  Each
Guarantor  agrees that the Guaranteed  Obligations may at any time and from time
to  time  exceed  the  Maximum  Guaranty  Liability  of such  Guarantor  without
impairing  this Guaranty or affecting the rights and remedies of the  Guaranteed
Party hereunder.

                (b) If and to the extent that any  Guarantor  shall,  under this
Guaranty  make a payment (a  "Guarantor  Payment")  of all or any portion of the
Guaranteed  Obligations,  then such Guarantor  shall be entitled to contribution
and  indemnification  from,  and  shall  be  reimbursed  by,  each of the  other
Guarantors  (collectively the "Contributing  Guarantors") in an amount, for each
such Contributing Guarantor,  equal to a fraction of such Guarantor Payment, the
numerator of which fraction is such Contributing Guarantor's Allocable Amount of
such  Guarantor  Payment and the  denominator  of which is the sum of all of the
Allocable  Amounts  of  such  Guarantor  Payment  of  all  of  the  Contributing
Guarantors.  As of any date of  determination  thereof  and with  respect to any
Guarantor Payment,  the "Allocable Amount" of each Contributing  Guarantor shall
be equal to the maximum amount of liability which could be asserted against such
Contributing  Guarantor  under this  Guaranty  with  respect  to such  Guarantor
Payment  without (i)  rendering  such  Contributing  Guarantor  insolvent,  (ii)
                                      -2-
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leaving such Contributing  Guarantor with unreasonably  small capital to conduct
its  business,  or (iii)  causing such  Contributing  Guarantor to have incurred
debts  beyond  its  ability to pay such  debts as they  mature.  As used in this
Section 2(b), the terms  "insolvent" and  "unreasonably  small capital" shall be
determined in accordance  with  Applicable  Laws.  This Section 2(b) is intended
only to define  the  relative  rights and  obligations  of the  Guarantors  with
respect to any and all Guarantor Payments, and nothing set forth in this Section
2(b) is intended to or shall otherwise modify,  affect or impair the obligations
of the  Guarantors,  jointly and severally,  to pay any or all of the Guaranteed
Obligations as and when the same shall become due and payable in accordance with
the terms of this Guaranty.  Each of the Guarantors hereby acknowledges that the
rights of contribution and indemnification  hereunder shall constitute assets in
favor of each Guarantor to which such contribution and  indemnification is owing
hereunder.  The agreements contained in this Section 2(b) shall continue in full
force and effect and may not be terminated or otherwise revoked by any Guarantor
until all of the Guaranteed Obligations have been indefeasibly paid in full, all
Commitments  under the Credit  Agreement  have  terminated  or expired,  and the
Credit  Agreement  and the other Loan  Documents  shall have been  terminated in
accordance with the terms thereof.

                3. Guaranty Absolute.  This Guaranty shall in all respects be an
absolute,  unconditional  and irrevocable  guaranty of payment of the Guaranteed
Obligations and each Guarantor  guarantees that the Guaranteed  Obligations will
be paid strictly in accordance  with the terms of the Loan Documents under which
they arise,  regardless  of any law,  regulation  or order now or  hereafter  in
effect in any  jurisdiction  affecting  any of such  terms or the  rights of the
Guaranteed  Party with respect  thereto.  The liability of each Guarantor  under
this Guaranty shall remain in full force and effect without regard to, and shall
not be  released,  suspended,  discharged,  terminated,  modified  or  otherwise
affected  by  any  circumstance  or  occurrence  whatsoever,  including  without
limitation any of the following  (whether or not any Guarantor  consents thereto
or has notice thereof): (i) any change in or waiver of the time, place or manner
of payment,  or any other term,  of any of the  Guaranteed  Obligations  or Loan
Documents,  any waiver of or any  renewal,  extension,  increase,  amendment  or
modification  of or addition,  consent or supplement to or deletion from, or any
other  action  or  inaction  under  or in  respect  of,  any of  the  Guaranteed
Obligations  or Loan  Documents or any other  document,  instrument or agreement
referred  to therein or any  assignment  or  transfer  of any of the  Guaranteed
Obligations  or  Loan  Documents;  (ii)  any  lack  of  validity,   legality  or
enforceability  of any of the  Guaranteed  Obligations  or Loan Documents or any
other  document,  instrument,  or  agreement  referred  to  therein  or  of  any
assignment  or transfer of any of the  foregoing;  (iii) any  furnishing  to the
Guaranteed  Party  of any  additional  collateral  for  any  of  the  Guaranteed
Obligations or any sale,  exchange,  release or surrender of, or realization on,
any  collateral  for any of the  Guaranteed  Obligations;  (iv) any  settlement,
release or compromise of any of the Guaranteed  Obligations  or Loan  Documents,
any collateral therefor,  or any liability of any other party (including without
limitation  any  other   guarantor)  with  respect  to  any  of  the  Guaranteed
Obligations or Loan  Documents,  or any  subordination  of payment of any of the
Guaranteed  Obligations to the payment of any other  indebtedness,  liability or
obligation  of the Borrower;  (v) any  bankruptcy,  insolvency,  reorganization,
composition,  adjustment,  merger,  consolidation,  dissolution,  liquidation or
                                      -3-
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other like proceeding or occurrence relating to the Borrower or any other change
in  the   ownership,   composition   or  nature  of  the   Borrower;   (vi)  any
non-perfection,  subordination,  release,  avoidability  or  voidability  of any
security interest,  security title, pledge,  collateral assignment or other lien
of the Guaranteed Party on any collateral for any of the Guaranteed  Obligations
or this  Guaranty;  (vii) any  application  of sums paid by the  Borrower or any
other person with respect to any of the  Guaranteed  Obligations,  except to the
extent actually applied against the Guaranteed  Obligations,  regardless of what
other  liabilities  of the  Borrower  remain  unpaid;  (viii) the failure of the
Guaranteed Party to assert any claim or demand or to enforce any right or remedy
against the Borrower or any other person  (including any other  guarantor of any
of the Guaranteed Obligations) under the provisions of any of the Loan Documents
or otherwise,  or any failure of the  Guaranteed  Party to exercise any right or
remedy  against  any  other  guarantor  of or  any  collateral  for  any  of the
Guaranteed  Obligations;  (ix) any other act or failure to act by the Guaranteed
Party which may adversely  affect any Guarantor;  or (x) any other  circumstance
which might  otherwise  constitute  a defense  against,  or a legal or equitable
discharge of, any Guarantor's liability under this Guaranty.

                4. Guaranty  Continuing;  Reinstatement.  This Guaranty shall in
all  respects  be a  continuing  and  irrevocable  guaranty of payment and shall
remain in full force and effect  until the  Termination  Date.  If claim is ever
made upon the Guaranteed  Party for repayment or recovery of any amount received
by the  Guaranteed  Party in  payment  or on  account  of any of the  Guaranteed
Obligations,  and if the  Guaranteed  Party repays all or part of said amount by
reason of (i) any judgment,  decree or order of any court or administrative body
having jurisdiction over the Guaranteed Party or any of its property or (ii) any
settlement or compromise of any such claim effected by the Guaranteed Party with
any such  claimant  (including  without  limitation  the  Borrower or a trustee,
conservator or receiver for the Borrower), then and in such event each Guarantor
agrees that any such judgment,  decree, order, settlement or compromise shall be
binding upon such Guarantor,  notwithstanding  any revocation or cancellation of
this Guaranty or of any of the Loan  Documents,  and each Guarantor shall be and
remain  liable to the  Guaranteed  Party  hereunder  for the amount so repaid or
recovered to the same extent as if such amount had never originally been paid to
the Guaranteed  Party and each  Guarantor's  obligations  and liabilities to the
Guaranteed Party under this Guaranty shall be reinstated to such extent and this
Guaranty and any  collateral  for this  Guaranty  shall remain in full force and
effect (or shall be reinstated) to such extent.  Each Guarantor hereby expressly
waives the benefit of any applicable  statute of limitations  and agrees that it
shall be liable  under this  Guaranty  whenever  the  Guaranteed  Party seeks to
enforce such liability against such Guarantor or its property.

                5. Waivers and  Consents.  Each  Guarantor  hereby  waives:  (i)
notice of acceptance of this Guaranty by the  Guaranteed  Party;  (ii) notice of
the  creation,  existence,  acquisition,  extension,  or  renewal  of any of the
Guaranteed Obligations; (iii) notice of the amount of the Guaranteed Obligations
outstanding from time to time,  subject,  however,  to each Guarantor's right to
make inquiry of the  Guaranteed  Party at reasonable  intervals to ascertain the
amount of  Guaranteed  Obligations  then  outstanding;  (iv) except as otherwise
expressly  required under the Loan Documents,  notice of any default or event of
default under any of the Loan Documents or with respect to any of the Guaranteed
Obligations or notice of 
                                      -4-
<PAGE>
any other  adverse  change in the  Borrower's  financial  condition  or means or
ability to pay any of the  Guaranteed  Obligations  or perform  its  obligations
under any of the Loan Documents or notice of any other fact which might increase
any Guarantor's risk hereunder; (v) notice of presentment,  demand, protest, and
notice of  dishonor  or  nonpayment  as to any  instrument;  (vi)  notice of any
acceleration  or other demand for payment of any of the Guaranteed  Obligations;
and (vii) all other notices and demands to which any Guarantor  might  otherwise
be  entitled  with  respect  to any of the  Guaranteed  Obligations  or the Loan
Documents or with respect to the  Guaranteed  Party's  enforcement of its rights
and remedies thereunder.  Each Guarantor further waives any right such Guarantor
may have,  by statute or  otherwise,  to require  the  Guaranteed  Party to seek
recourse first against the Borrower or any other person,  or to realize upon any
collateral for any of the Guaranteed  Obligations,  as a condition  precedent to
enforcing such Guarantor's  liability and obligations  under this Guaranty,  and
each Guarantor further waives any defense arising by reason of any incapacity or
other  disability  of the Borrower or by reason of any other  defense  which the
Borrower may have on any of the Guaranteed  Obligations or under any of the Loan
Documents. Each Guarantor consents and agrees that, without notice to or consent
by any  Guarantor  and without  affecting  or  impairing  the  liability  of any
Guarantor  under this Guaranty,  the Guaranteed  Party may compromise or settle,
extend  the  period  of  duration  or the time  for the  payment,  discharge  or
performance  of any of the  Guaranteed  Obligations  or Loan  Documents,  or may
refuse  to  enforce  or may  release  all or  any  parties  to any or all of the
Guaranteed   Obligations  (including  without  limitation  any  other  guarantor
thereof)  or any  collateral  therefor,  or may grant other  indulgences  to the
Borrower  or such  other  parties  in respect  thereof,  or may waive,  amend or
supplement  in any manner the  provisions  of any of the Loan  Documents  or any
other  document,  instrument  or  agreement  relating to or securing  any of the
Guaranteed  Obligations (other than this Guaranty),  or may release,  surrender,
exchange,  modify,  or  compromise  any and all  collateral  securing any of the
Guaranteed  Obligations or in which the Guaranteed  Party may at any time have a
lien,  or may  refuse  to  enforce  its  rights  or may make any  compromise  or
settlement or agreement therefor,  in respect of any and all of such collateral,
or with any party to any of the  Guaranteed  Obligations or Loan  Documents,  or
with any other person, or may release or substitute any one or more of the other
endorsers or guarantors of the Guaranteed  Obligations  whether  parties to this
Guaranty or not, or may exchange,  enforce,  waive or release any collateral for
any  guaranty  of any of the  Guaranteed  Obligations.  Each  Guarantor  further
consents and agrees that the Guaranteed  Party shall not be under any obligation
to marshal any assets in favor of such Guarantor or against or in payment of any
of the Guaranteed Obligations.

                6.  Subrogation and Other Rights.  Each Guarantor agrees that no
payment,   performance  or  enforcement  of  such  Guarantor's  liabilities  and
obligations  under this Guaranty shall cause such  Guarantor,  by subrogation or
otherwise,  to acquire any of the Guaranteed Party's rights against the Borrower
or any property of the  Borrower  (or any  interest in such  rights)  unless and
until the Guaranteed Party has received full and indefeasible  payment of all of
the Guaranteed Obligations.

                7.  Cross-Collateralization.  Each  Guarantor's  obligations and
liabilities to the Guaranteed  Party under this Guaranty shall be secured by (i)
any and all property pledged by
                                      -5-
<PAGE>
such  Guarantor  to the  Guaranteed  Party or in which the  Guaranteed  Party is
granted a Lien  pursuant  to the  Security  Agreement  or any  other  Collateral
Document  from  such  Guarantor  to the  Guaranteed  Party and any and all other
security interests,  security titles,  pledges,  collateral assignments or other
Liens which the Guaranteed  Party may now or hereafter have or acquire in, to or
on any real or personal  property assets of such Guarantor,  whether such assets
now exist or are hereafter acquired,  except to the extent that such Guarantor's
obligations and liabilities  hereunder are expressly  excluded from the coverage
of any such  Lien  under  the  express  terms of the  mortgage,  security  deed,
security agreement,  pledge agreement,  collateral  assignment or other document
which granted or grants such Lien.

                8. Guarantor Due Diligence and Benefit.  Each Guarantor is fully
aware of the financial condition, assets and prospects of the Borrower, and each
Guarantor is  executing  and  delivering  this  Guaranty  based solely upon such
Guarantor's  own  independent  investigation  thereof  and in no part  upon  any
representation,  warranty or statement of the  Guaranteed  Party with respect to
the Borrower's financial condition,  assets or prospects. Each Guarantor is in a
position to and hereby  assumes full  responsibility  for  obtaining any and all
information concerning the Borrower's financial condition,  assets and prospects
as such  Guarantor  may now or hereafter  deem  material to such its decision to
enter into and become  liable  under this  Guaranty  and such  Guarantor  is not
relying upon, nor does such Guarantor  expect the Guaranteed Party to furnish it
with any  information  which may be now or hereafter in the  Guaranteed  Party's
possession  concerning the Borrower's financial condition,  assets or prospects.
Each  Guarantor  hereby  knowingly  accepts the full range of risks  encompassed
within a contract  of  guaranty,  which  risks such  Guarantor  understands  may
include,  without  limitation,  the  possibility  that the  Borrower  may  incur
additional  indebtedness to the Guaranteed Party for which such Guarantor may be
liable hereunder after the Borrower's financial condition or means or ability to
pay its lawful debts when they fall due has deteriorated. Each Guarantor further
acknowledges and agrees that any credit or other financial accommodations now or
hereafter  extended  by the  Guaranteed  Party to the  Borrower  and any and all
forbearances  with respect to the  Borrower or its assets  which the  Guaranteed
Party may now or hereafter grant are and will be of direct interest, benefit and
advantage to such Guarantor.

                9.  Guaranteed  Party's  Accounts  and Records;  Application  of
Payments.  Each Guarantor agrees that, in the absence of manifest error, any and
all books and records relating to the Guaranteed  Obligations which are prepared
and maintained by the Guaranteed  Party shall constitute prima facie evidence of
the existence and amount of the  Guaranteed  Obligations.  In the event that the
Guaranteed  Party sends to the  Borrower  any  periodic or other  statements  of
account  with  respect to any or all of the  Guaranteed  Obligations,  each such
statement  rendered by the  Guaranteed  Party shall,  in the absence of manifest
error, be deemed final,  binding and conclusive  upon each Guarantor  unless the
Guaranteed  Party is notified by the Borrower in writing to the contrary  within
thirty (30) days after the date such statement was sent by the Guaranteed  Party
to the Borrower (and each such notice shall only be deemed an objection to those
items specifically  objected to therein).  Each Guarantor irrevocably waives the
right to direct the  application of any and all payments and  collections at any
time  hereafter  received  by the  Guaranteed  Party  from or on  behalf  of the
Borrower,
                                      -6-
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any Guarantor or otherwise with respect to any of the Guaranteed Obligations and
each Guarantor  does hereby  irrevocably  agree that the Guaranteed  Party shall
have the  continuing  exclusive  right to apply  and  re-apply  any and all such
payments and collections  received at any time hereafter by the Guaranteed Party
against the  Guaranteed  Obligations  in such manner and order as the Guaranteed
Party may deem advisable,  notwithstanding  any contrary entry by the Guaranteed
Party upon any of its books and records.

                10. Automatic  Acceleration of Guaranty.  Upon the occurrence of
any Event of  Default  described  in  Section  8.1(f),  (g) or (h) of the Credit
Agreement, all of the Guaranteed Obligations shall be deemed immediately due and
payable,  without notice or demand of any kind by the Guaranteed Party, and each
Guarantor  agrees  immediately  to  pay  the  Guaranteed  Obligations  in  full,
irrespective  of whether any or all of the  Guaranteed  Obligations  can then be
accelerated  against  the  Borrower  and  irrespective  of any  right  which the
Borrower  then  may have  under  any  bankruptcy,  receivership,  insolvency  or
moratorium law to cure defaults and reinstate the maturities of the Obligations.

                11.  Notices  to  Guarantors.  All  notices,  demands  and other
communications  hereunder  or  under  any of the  other  Loan  Documents  by the
Guaranteed  Party to any Guarantor  shall be effective (i) if given by telecopy,
when such  communication is transmitted to the telecopy number set forth beneath
such  Guarantor's  signature  below (with such  telecopy  promptly  confirmed by
delivery of a copy by personal  delivery or U.S.  mail as otherwise  provided in
this Section),  (ii) if given by mail within the United States of America, three
(3) days after such  communication  is deposited in the United  States mail with
first  class  postage  prepaid,  return  receipt  requested  addressed  to  such
Guarantor at its address set forth  beneath such  Guarantor's  signature  below,
(iii) if sent for  overnight  delivery  within the  United  States of America by
Federal Express or other reputable national overnight delivery service,  one (1)
Business Day after such communication is entrusted to such service for overnight
delivery and with recipient signature  required,  addressed as aforesaid or (iv)
if given by any other means,  when delivered at the address of the party to whom
such notice is being delivered.  Any Guarantor may designate a different address
or  telecopy  number  for such  Guarantor's  receipt  of such  notices  or other
communications  but no such  change  shall be  effective  unless  and  until the
Guaranteed Party actually receives written notice thereof from such Guarantor.

                12.  Collection  Costs.  Each  Guarantor  shall be liable to the
Guaranteed  Party for,  and shall pay to the  Guaranteed  Party on  demand,  all
reasonable costs (including  without limitation  reasonable  attorney's fees and
expenses)  incurred  by the  Guaranteed  Party in  enforcing  performance  of or
collecting any payments due under this Guaranty.

                13. Assignment and Transfer. This Guaranty shall be binding upon
each Guarantor and its  successors and permitted  assigns and shall inure to the
benefit of and be  enforceable  by the  Guaranteed  Party and its successors and
permitted  assigns.  Without limiting the generality of the preceding  sentence,
the Guaranteed  Party may assign or grant  participations  in all or any part of
the Guaranteed Obligations,  whereupon such assignee or participant shall become
entitled to all of the rights in respect thereof granted to the Guaranteed Party
herein.
                                      -7-
<PAGE>
                14.  Governing  Law.  This  Guaranty  shall be  governed  by the
internal laws of the State of New York  (without  giving effect to its conflicts
of law rules).

                15.   Subordination  of  Borrower's  and  other  Credit  Party's
Obligations to the Guarantors. As an independent covenant, each Guarantor hereby
expressly  covenants and agrees for the benefit of the Guaranteed Party that all
present or future  indebtedness,  obligations and liabilities of the Borrower or
any other Credit Party (including without limitation any other Guarantor) to any
Guarantor of whatsoever description (collectively, the "Junior Claims") shall be
subordinate and junior in right of payment to all Obligations of the Borrower or
any such other Credit Party to the Guaranteed Party  (collectively,  the "Senior
Claims"),  effective upon the occurrence and during the  continuance of an Event
of Default under the Credit  Agreement.  If an Event of Default under the Credit
Agreement shall occur,  then,  unless and until such Event of Default shall have
been cured or shall have  ceased to exist,  no direct or  indirect  payment  (in
cash,  property,  securities,  by  set-off  or  otherwise)  shall be made by the
Borrower  or any other  Credit  Party to any  Guarantor  on account of or in any
manner in respect of any Junior Claim except such payments and distributions the
proceeds  of which  shall be  applied to the  Senior  Claims.  In the event of a
Proceeding (as  hereinafter  defined),  all Senior Claims shall first be paid in
full before any direct or indirect payment or distribution  (in cash,  property,
securities,  by set-off or otherwise)  shall be made to any Guarantor on account
of or in any manner in respect of any Junior  Claim  except  such  payments  and
distributions  the proceeds of which shall be applied to the Senior Claims.  For
the  purposes  of the  previous  sentence,  a  "Proceeding"  shall  occur if the
Borrower or any other Credit Party shall make an  assignment  for the benefit of
creditors, file a petition in bankruptcy, have entered against or in favor of it
an order  for  relief  under the  Bankruptcy  Code or  similar  law of any other
jurisdiction,  generally  fail to pay its debts as they come due  (either  as to
number or amount),  admit in writing its inability to pay its debts generally as
they mature, make a voluntary assignment for the benefit of creditors,  commence
any   proceeding   relating  to  it  under  any   reorganization,   arrangement,
readjustment  of  debt,  dissolution  or  liquidation  law  or  statute  of  any
jurisdiction,  whether now or hereafter in effect,  or by any act,  indicate its
consent  to,  approval  of or  acquiescence  in any  such  proceeding  or in the
appointment  of any  receiver  of, or trustee or  custodian  (as  defined in the
Bankruptcy  Code) for itself,  or any  substantial  part of its  property,  or a
trustee or a receiver  shall be  appointed  for the Borrower or any other Credit
Party or for a  substantial  part of the  property of the  Borrower or any other
Credit Party, or a petition under any bankruptcy,  reorganization,  arrangement,
readjustment  of  debt,  dissolution  or  liquidation  law  or  statute  or  any
jurisdiction  (whether now or hereafter  in effect)  shall be filed  against the
Borrower or any other Credit Party. In the event any direct or indirect  payment
or distribution is made to any Guarantor in contravention of this Section,  such
payment or distribution shall be deemed received in trust for the benefit of the
Guaranteed  Party and shall be immediately paid over to the Guaranteed Party for
application  against the Senior Claims.  Each  Guarantor  agrees to execute such
additional  documents as the Guaranteed Party may reasonably request to evidence
the subordination provided for in this Section.

                16.   Miscellaneous.   (a)  This  Guaranty  (together  with  any
collateral  documents  executed by any Guarantor to secure its  obligations  and
liabilities hereunder) constitutes the 
                                      -8-
<PAGE>
sole and entire  agreement  between the Guarantors and the Guaranteed Party with
respect to the subject  matter  hereof and  supersedes  and replaces any and all
prior agreements,  understandings,  negotiations or correspondence  between them
with respect thereto,  including  without  limitation any and all prior guaranty
agreements  executed  by any  Guarantor  in favor of the  Guaranteed  Party with
respect to any or all of the Guaranteed Obligations.

                (b) Time is of the essence of this Guaranty.

                (c) Words importing the singular number  hereunder shall include
the plural number and vice versa and any pronouns used herein shall be deemed to
cover all  genders.  The term  "person"  as used  herein  means any  individual,
corporation,  partnership,  joint  venture,  association,  joint-stock  company,
trust,  unincorporated  association,  or government  (or any agency or political
subdivision thereof).

                (d) Wherever  possible,  any provision in this Guaranty which is
prohibited or unenforceable in any jurisdiction  shall, as to such jurisdiction,
be  ineffective  only to the  extent  of such  prohibition  or  unenforceability
without  invalidating the remaining  provisions hereof, and any such prohibition
or  unenforceability  in any one  jurisdiction  shall not  invalidate  or render
unenforceable such provision in any other jurisdiction.

                (e) No  amendment or waiver of any  provision of this  Guaranty,
nor consent to any departure by any Guarantor  therefrom,  shall be effective or
binding upon the Guaranteed  Party unless the Guaranteed  Party shall first have
given written consent thereto. Any such amendment, waiver or consent which is so
granted by the Guaranteed Party shall apply only to the specific  occasion which
is the subject of such  amendment,  waiver or consent and shall not apply to the
occurrence of the same or any similar event on any future  occasion.  No failure
on the part of the Guaranteed Party to exercise,  and no delay by the Guaranteed
Party in exercising,  any right hereunder shall operate as a waiver thereof, nor
shall any single or partial  exercise of any right hereunder  preclude any other
or further exercise thereof or the exercise of any other right by the Guaranteed
Party.  No notice to or demand on any  Guarantor  in any case by the  Guaranteed
Party  hereunder shall entitle such Guarantor to any further notice or demand in
any similar or other  circumstances  or constitute a waiver of the rights of the
Guaranteed Party to take any other or future action in any circumstances without
notice or demand. The remedies provided to the Guaranteed Party in this Guaranty
are cumulative and not exclusive of any other remedies provided by law.

                (f) This  Guaranty  may be executed in one or more  counterparts
and each such counterpart shall constitute an original and all such counterparts
together shall constitute one and the same instrument.

                (g) All Section headings herein are for convenience of reference
only and shall not limit or otherwise  affect the meaning or  interpretation  of
the provisions of this Guaranty.

                17. Jury Trial Waiver;  Consent to Jurisdiction and Venue.  EACH
GUARANTOR  HEREBY WAIVES ANY RIGHT SUCH  GUARANTOR MAY HAVE
                                      -9-
<PAGE>
UNDER ANY  APPLICABLE  LAW TO A TRIAL BY JURY WITH  RESPECT TO ANY SUIT OR LEGAL
ACTION WHICH MAY BE COMMENCED BY OR AGAINST ANY GUARANTOR,  THE GUARANTEED PARTY
OR  THE  BORROWER   CONCERNING  THE  INTERPRETATION,   CONSTRUCTION,   VALIDITY,
ENFORCEMENT OR PERFORMANCE OF THIS GUARANTY OR ANY OF THE LOAN DOCUMENTS. IN THE
EVENT ANY SUCH SUIT OR LEGAL ACTION IS COMMENCED BY THE GUARANTEED  PARTY,  EACH
GUARANTOR  HEREBY  EXPRESSLY  AGREES,  CONSENTS  AND  SUBMITS  TO  THE  PERSONAL
JURISDICTION  OF ANY STATE OR FEDERAL COURT SITTING IN THE CITY AND STATE OF NEW
YORK, BOROUGH OF MANHATTAN,  WITH RESPECT TO SUCH SUIT OR LEGAL ACTION, AND EACH
GUARANTOR  ALSO  EXPRESSLY  CONSENTS AND SUBMITS TO AND AGREES THAT VENUE IN ANY
SUCH SUIT OR LEGAL ACTION IS PROPER IN SAID COURTS AND COUNTY AND EACH GUARANTOR
HEREBY  EXPRESSLY  WAIVES ANY AND ALL PERSONAL RIGHTS UNDER APPLICABLE LAW OR IN
EQUITY TO OBJECT TO THE JURISDICTION AND VENUE OF SAID COURTS.  THE JURISDICTION
AND VENUE OF THE COURTS  CONSENTED  AND  SUBMITTED  TO AND  AGREED  UPON IN THIS
SECTION ARE NOT EXCLUSIVE BUT ARE CUMULATIVE AND IN ADDITION TO THE JURISDICTION
AND VENUE OF ANY OTHER COURT UNDER ANY APPLICABLE LAW OR IN EQUITY.

                  [Remainder of page intentionally left blank]
                                      -10-
<PAGE>
                IN WITNESS  WHEREOF,  the Guarantors have executed and delivered
this Guaranty by its duly authorized officer as of the date first above written.

                                        ARIZONA REPAIR SERVICES, INC.


                                         By: /s/ Greg Roeper
                                            ------------------------------------
                                         Title: CFO and V.P.
                                               ---------------------------------

                                        Address for Notices:
                                        --------------------

                                        8300 East Raintree Drive
                                        Scottsdale, Arizona  85260
                                        Attn:  Greg Roeper
                                        Telecopy: (602) 483-0144

                                        ENHANCED SYSTEMS, INC.


                                         By: /s/ Greg Roeper
                                            ------------------------------------
                                         Title: Secretary and Treasurer
                                               ---------------------------------

                                        Address for Notices:
                                        -------------------
   
                                        8300 East Raintree Drive
                                        Scottsdale, Arizona  85260
                                        Attn:  Greg Roeper
                                        Telecopy: (602) 483-0144

SECTION 15 OF THE FOREGOING
GUARANTY ACKNOWLEDGED AND
AGREED TO:

VODAVI COMMUNICATIONS
SYSTEMS, INC.


By: /s/ Greg Roeper
   ------------------------------------
Title: CFO and V.P.
      ---------------------------------
                                      -11-