SECTION 1. Section 4 of Chapter 64I of the General Laws is hereby amended by striking out, in lines 25-31, the words “For purposes of such determination, the sales price of any motor vehicle, except a motor vehicle purchased from a vendor registered under this chapter who is regularly engaged in the business of making sales at retail of such motor vehicles, shall be the actual amount paid by the purchaser to the vendor for the motor vehicle or the clean trade-in value of the motor vehicle, whichever is greater, regardless of the actual condition of the vehicle.” and inserting in place thereof the following words:-

“For purposes of such determination, the sales price of any motor vehicle, except a motor vehicle purchased from a vendor registered under this chapter who is regularly engaged in the business of making sales at retail of such motor vehicles, shall be the actual amount paid by the purchaser to the vendor for said motor vehicle as documented by a notarized bill of sale. If a notarized bill of sale is not provided, the sales price shall be determined by the clean trade-in value of the motor vehicle.”