(a) Notwithstanding any other law, the finance charge, exclusive of insurance and other benefits and official fees, shall not exceed the following rates:

Class 1. Any new motor vehicle designated by the manufacturer by a year model not earlier than the year in which the sale is made and all vehicles not previously titled -- $10.00 per $100.00 per year.

Class 2. Any new motor vehicle not in Class 1 and any used motor vehicle designated by the manufacturer by a year model of the same or not more than two years prior to the year in which the sale is made -- $13.00 per $100.00 per year.

Class 3. Any used motor vehicle not in Class 2 and designated by the manufacturer by a year model not more than four years prior to the year in which the sale is made -- $15.00 per $100.00 per year.

Class 4. Any used motor vehicle not in Class 2 or Class 3 and designated by the manufacturer by a year model more than four years prior to the year in which the sale is made -- $17.00 per $100.00 per year.

(b) Such finance charge shall be computed on the unpaid balance on contracts payable in successive monthly payments substantially equal in amount. Such finance charge may be computed on the basis of a full month for any fractional month period in excess of ten days. A minimum finance charge of $25.00 may be charged on any retail installment transaction. As used in this subsection, the term "unpaid balance" shall be determined in accordance with Section 226.8(c) of Regulation Z promulgated by the Board of Governors of the Federal Reserve System pursuant to Title I (Truth in Lending Act) and Title V (General Provisions) of the Consumer Credit Protection Act (Public Law 90-321, 82 Stat. 146, et seq.), as the same existed upon its becoming effective on July 1, 1969.

(c) When a retail installment contract provides for unequal or irregular installment payments, the finance charge may be at a rate which will provide the same yield as is permitted on monthly payment contracts under subsections (a) and (b) of this Code section, having due regard for the schedule of payments. Notwithstanding the foregoing, a seller who computes a finance charge on an actuarial basis may charge a finance charge, exclusive of insurance and other benefits and official fees, which, when calculated according to the actuarial method, does not exceed the yield which would have been permitted on monthly contracts under subsections (a) and (b) of this Code section, having due regard for the schedule of payments; provided, however, that when a seller computes the finance charge according to the actuarial method, then for purposes of computing the rate the entire term of the contract shall be considered to be the number of whole months within the scheduled payment period, disregarding any odd days.

(d) Notwithstanding the provisions of subsection (a) of this Code section, a buyer and a seller may establish any finance charge agreed upon in writing by the parties where the amount financed is more than $5,000.00.

(e) Any sales finance company may purchase or acquire or agree to purchase or acquire from any seller any contract on such terms and conditions as may be agreed upon between them. Unless the buyer has notice of the assignment of his contract, payment thereunder made by the buyer to the last known holder of such contract shall be binding upon all subsequent holders.

(f) In no event will any such assignment bar any right of action against the seller arising as a result of this article nor will any such assignment bar any defense against the sales finance company or other assignee arising as a result of subsection (b) of Code Section 10-1-38.