A. If, at the time of a sale, it is impractical for the buyer to establish the actual amount of the property being purchased which is to be resold, the tax shall be paid on the entire amount of the sale, either if the buyer has reason to believe that a majority of the tangible personal property will not be resold, or if the buyer cannot determine whether or not a majority of the tangible personal property will be resold. If any portion of the property is later resold without having first been used by the buyer, the buyer may apply for a refund of the taxes attributable to this property, within 4 years of the date of purchase.
B. If no tax is paid upon the purchase of tangible personal property pursuant to §A of this regulation, the buyer shall include the cost of that portion converted to the buyer's personal use as a purchase subject to the sales and use tax on the return to be filed for the period in which the property was converted.
C. The procedure described in §B shall also be followed by any person who purchases tangible personal property for resale without paying the tax, and who subsequently converts the property to personal use.