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. The proof of sale for a vehicle from a dealer is the Retail Certificate of Sale (MV-50) ("Dealer's Bill of Sale").Use this free form for private transactions. It comes in a printable PDF format, and you can quickly fill it out using your completer. A New York motor vehicle bill of sale provides proof that a motor vehicle has been legally sold and acquired in the State of New York. Prepare Your RV for Sale; 2. Get an Appraisal; 3. A New York Trailer Bill of Sale helps streamline the registration process and proves the transfer of ownership if a dispute arises. Clearly print or type all information, except signatures. Use our NY bill of sale forms to prove the transfer of ownership of property from seller to buyer in the state of New York.