Option 1. Computing the refinance charge on the amount of the installment payment or payments or part thereof, which is refinanced for the period of time, for which each payment or part thereof is extended or deferred at the following rates on contracts originally in the respective classification of motor vehicles set forth in the preceding section of this act:
Class I. One percent (1%) per month.
Class II. One and one-half percent (1 1/2 %) per month.
Class III. Two percent (2%) per month.
Such refinance charges may be computed on the basis of a full month for any fractional month period in excess of ten (10) days.
Option 2. Computing the refinance charge on the amount obtained by adding to the unpaid time balance of the contract, charges for insurance and other charges incidental to refinancing, by adding unpaid default charges, which may be accrued, and by deducting any rebate which may be due to the buyer for prepayment incidental to refinancing, at the rate of the finance charge in the original contract, for the term of the renewal contract, and subject to the provisions of this act governing computation of the original finance charge: Provided, however, That the provisions of this act governing minimum finance charges and minimum prepayment rebate shall not apply in calculating refinance charges on the contract renewed under this method of computation.
69 P.S. § 620