An RV Bill of Sale is a legal document that serves as proof of the sale and transfer of ownership of a recreational vehicle (RV) from a seller to a buyer. This is typically one of the first items you'll put on the bill of sale.A Recreational Vehicle (RV) Bill of Sale is required anytime an RV is sold or transferred between a seller and a buyer. How do I fill this out? MV-912: Vehicle Bill of Sale (PDF). English. Use this form to show proof of a vehicle ownership transfer through a private sale. Download. Visit Department of Motor Vehicles website.