Texas Finance Code - FIN § 348.115. Charge for Other Amendment

(a) If the unpaid balance of a retail installment contract is extended, renewed, restated, or rescheduled under this subchapter and Section 348.114 does not apply, the holder may collect an amount computed on the principal balance of the amended contract for the term of the amended contract at the time price differential for a retail installment contract that is applicable after reclassifying the motor vehicle by its model year at the time of the amendment.

(b) The principal balance of the amended contract is computed by:

(c) The provisions of this chapter relating to minimum charges under Section 348.104 and acquisition costs under the refund schedule under Section 348.120 do not apply in computing the principal balance of the amended contract.