1.    Except as otherwise provided in subsection 2, retailers shall add the tax imposed under this chapter, or the average equivalent thereof, to the sales price or charge, and when added, such tax constitutes a part of such price or charge, is a debt from the consumer or user to the retailer until paid, and is recoverable at law in the same manner as other debts.

A retailer shall determine the amount of tax charged to and received from each purchaser by use of a formula that applies the applicable tax rate to each taxable item or total purchase and the product must be carried to the third decimal place. Amounts of tax less than one-half of one cent must be disregarded and amounts of tax of one-half of one cent or more must be considered an additional cent of tax. When a local sales tax applies, the determination of tax charged to and received from each customer will be applied to the aggregated state and local taxes.

2.    On retail sales of manufactured homes used for residential or business purposes, except as provided in subsection 35 of section 57-39.2-04, retailers shall add the tax imposed under this chapter, or the average equivalent thereof, to the sales price or charge, and when added, such tax constitutes a part of such price or charge, is a debt from the consumer or user to the retailer until paid, and is recoverable at law in the same manner as other debts. In adding such tax to the price or charge, retailers shall add to it three percent of such price or charge.