When selling a vehicle, the seller must sign and handprint their name on the proof of ownership document. A Pennsylvania vehicle bill of sale is a legal document formalizing the sale and purchase of a motor vehicle between a buyer and seller.This process typically involves reviewing and signing documents related to financing, registration, and insurance. What Documentation Should I Receive When I Purchase a Used Car in PA? ❖ Form MV-1 must be completed and a check or money order payable to the Commonwealth of. You'll need to sign the car purchase agreement (or dealer bill of sale), the title, an odometer statement, and sometimes a damage disclosure statement. See our free, printable Pennsylvania Vehicle Bill of Sale below. It's available in both PDF and Word formats.