The provisions of §§ 46.2-1158 and 46.2-1539 requiring inspection of any motor vehicle prior to sale at retail shall not apply to any person conducting a public auction for the sale of motor vehicles at retail, provided that the individual, firm, or business conducting the auction shall not have taken title to the vehicle, but is acting as an agent for the sale of the vehicle. Nor shall the provisions of §§ 46.2-1158 and 46.2-1539 requiring inspection of any motor vehicle prior to sale at retail apply to any (i) new motor vehicle sold on the basis of a special order placed by a dealer with a manufacturer or dealer outside the Commonwealth on behalf of a customer who is a nonresident of the Commonwealth and takes delivery outside the Commonwealth, (ii) motor vehicle sold on the basis of a special order placed with a dealer or manufacturer outside the Commonwealth by a dealer who makes modifications to such vehicle prior to delivery to the first retail customer who takes delivery outside the Commonwealth, or (iii) new motor vehicle that has previously been inspected and displays a valid Virginia state inspection sticker. Nor shall the provisions of §§ 46.2-1158 and 46.2-1539 requiring inspection of any trailer prior to sale at retail apply to the sale of five or more used trailers with a gross weight of more than 10,000 pounds to the same buyer, provided that the trailers have a valid safety inspection. The provisions of this section shall also apply to watercraft trailers.