31-1-501. Late payment charges -- accounts receivable for merchandise sold at retail. (1) Notwithstanding 31-1-106 or 31-1-107, a person who sells goods, as defined in 31-1-202, at retail to a retail buyer who promises to pay for such goods upon presentation of the bill therefor, may charge and collect a late payment charge not greater than 1 1/2% per month on all money due on all accounts from 30 days after the date on which the obligation of the buyer to pay is incurred.

(2) The late payment charge provided in this section may be charged only if at the time the obligation was incurred the seller did not intend to extend any credit beyond 30 days and any late payment of the obligation was unintended.

(3) The provisions of this section do not apply to money due for intangible services, for services regulated by the public service commission, for real property, for health care services, or for retail installment sales contracts or retail charge account agreements regulated under Title 31, chapter 1, part 2.