The form consists of the significant vehicle, buyer, seller, and sale data, along with affirming signatures from both parties. Learn how to sell a travel trailer in Texas with our comprehensive RV Bill of Sale guide.Get step-by-step instructions, key documents, and FAQs. A Texas Trailer Bill of Sale is a legal document used when transferring ownership of a trailer. Instructions. This form must be submitted with the Rebuilt Vehicle Statement (Form VTR-61) when submitting a new application. A bill of sale allows the seller and the buyer to complete the transfer of ownership in a legal and safe way. A bill of sale is a legal document that outlines the purchase of property between a buyer and seller. It commonly includes both parties' information. The Texas bill of sale form verifies the elemental facts of the sale of personal property in exchange for a predetermined compensatory amount. The seller must provide various documents to complete a vehicle sale and transfer ownership to the buyer.