This form can be faxed on demand from 1-888-232-7033 or downloaded through the Texas Department of Motor Vehicles website. Supporting Evidence (if applicable).Though standard form bill of sales are available online and from your local county tax collector's office, it's also perfectly acceptable to write your own. To complete a title transfer, gather the required documents, such as the original title and bill of sale. The form consists of the significant vehicle, buyer, seller, and sale data, along with affirming signatures from both parties. Sign the buyer's application for title: When selling a car in Texas, you'll need to sign the Buyer's Application for Title, which is Form 130U.