The seller must complete all applicable information and sign this form. The Bill of Sale or Even-Trade Bill of Sale must be notarized.Learn about bill of sale requirements for the state of Missouri. Includes free Missouri bill of sale templates for cars, trucks, boats, firearms, and more. Learn about bill of sale laws and requirements for the state of Texas. Get templates for buying and selling high-value items like cars, boats, and firearms. A motor vehicle bill of sale is between a buyer and a seller of a car, truck, or motorcycle. It is signed as the last step in the sales process. How to fill out the Texas Firearm Bill of Sale Document Template? The Missouri general bill of sale is a legal contract between a buyer and seller over the ownership of personal property.