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. A Pennsylvania Trailer Bill of Sale is a critical document that can help protect your legal rights.A Pennsylvania vehicle bill of sale is a legal document formalizing the sale and purchase of a motor vehicle between a buyer and seller. The Pennsylvania bill of sale form acknowledges the transfer of possession of a piece of personal property for an agreedupon sum of money. A Pennsylvania bill of sale documents the transfer of ownership of a motor vehicle, boat, gun, or other valuable asset. How to get a trailer title with a bill of sale? Application (Form MV-1) – An owner completes this document to apply for a trailer registration and title. 3. How to fill out the Pennsylvania Vehicle Bill of Sale form? This form is used to obtain a Pennsylvania Certificate of Title for vehicles not currently titled in Pennsylvania, or which were repossessed (1. How to fill out the Pennsylvania Motor Vehicle Bill of Sale Form?