(1) Refunds. The price of tangible personal property or taxable services returned by a purchaser when the price and the sales tax collected are refunded in cash or by credit.

(2) Bad debts charged off. Taxable sales which are represented by accounts not secured by conditional sales contract, rental purchase contract or security interest, and which are found to be worthless and are actually and properly charged off as bad debts for the purpose of the income tax imposed by the laws of the State; provided, however, that if such amounts are thereafter collected by the taxpayer, a tax shall be paid on the amount so collected.

(3) Interest and finance charges. The amount of interest or finance charges on credit extended in connection with any sale, if the interest or finance charges are separately stated from the price.

(1) Vendor’s fee. A retailer’s collection and remittance expense equal to one and thirty-five one-hundredths (1 35/100%) of the sum of the sales tax computed, and any excess tax collected may be taken as a credit against sales tax paid, on or before the due date. Such vendor’s fee shall be forfeited for any sales tax that is not reported and paid by the due date. Forfeiture of the vendor’s fee shall be prima facie evidence that the taxpayer was in violation of this Article.

(2) Amounts previously paid pursuant to a tax levied by a municipality may be credited against the tax due on transactions or items other than construction materials as follows: