Information and Instructions. • Submit this form within 30 days of the vehicle's date of transfer to help protect yourself from liability for criminal.A Texas Bill of Sale Vehicle Form is a formal document used to record the sale and transfer of ownership of a vehicle from one party to another. County of Harris. §. Information you can expect to fill out includes the car's VIN, make, and model, the name and permanent address of each party involved, and the sales amount. A Texas Vehicle Purchase Agreement is a legally binding document that outlines the terms and conditions of a vehicle sale in Texas. You need to complete the remainder of the title application that the seller provides to you. ☐ - Buyer and not included in the exchange. Even though it is not a legal requirement in Texas, you have every reason to complete a bill of sale when selling your car. This should include the sale date and odometer reading.