Chapter 1: General Registration Information. A motor vehicle bill of sale is between a buyer and a seller of a car, truck, or motorcycle.It is signed as the last step in the sales process. How do I fill this out? A California motor vehicle bill of sale is part of the vehicle registration process. Use a free template to write your own bill of sale. If you are completing a bill of sale to satisfy a vehicle registration requirement, the law requires that you provide a copy to the DMV. Get high-quality Used Auto Bill of Sale forms for private vehicle deals. Instantly downloadable and printable for your convenience. Whether you're buying or selling a vehicle, boat, or personal property, our template makes it easy to set up, fill out, and sign a clear bill of sale.