15-68-103. Presumption of taxability -- value -- rules. (1) In order to prevent evasion of the sales tax or use tax and to aid in its administration, it is presumed that:

(a) all sales by a person engaging in business are subject to the sales tax or use tax; and

(b) all property bought or sold by any person for delivery into this state is bought or sold for a taxable use within this state.

(2) In determining the amount of use tax due on the use of property or services, it is presumed, in the absence of preponderant evidence of another value, that value means the total amount of property or service or the reasonable value of other consideration paid for the use of the property or service, exclusive of any type of time-price differential. However, in an exchange in which the amount of money paid does not represent the value of the property or service purchased, the use tax must be imposed on the reasonable value of the property or service purchased.

(3) The department shall adopt rules providing for the payment of the sales tax and use tax based on a rounding method.