The service charge shall be inclusive of all charges incident to investigating and making the retail installment contract or charge agreement and for the privilege of making the installment payments thereunder and no other fee, expense or charge whatsoever shall be taken, received, reserved, or contracted therefor from the buyer, except for any vehicle dealer administrative fee under RCW
46.68.440(1) or for any vehicle dealer documentary service fee under RCW
46.70.180(2).
(1) The service charge, in a retail installment contract, shall not exceed the dollar amount or rate agreed to by contract and disclosed under RCW
63.14.040(1)(h).
(2) The service charge in a retail charge agreement, revolving charge agreement, lender credit card agreement, or charge agreement, shall not exceed the schedule or rate agreed to by contract and disclosed under RCW
63.14.120(1). If the service charge so computed is less than one dollar for any month, then one dollar may be charged.