Bill of sale that states: In this article, we’ll break down the basics of a motor vehicle bill of sale and explain why it’s an important document to have in case of any legal proceedings. You will also need to either provide the buyer with your valid certificate of inspection (coi) or inform them they will need to have the vehicle inspected before they can register and insure it. Date purchased, vehicle’s model year, make, model and serial number; When a vehicle owned by an estate is sold to a third party, a bill of sale (signed by the estate executor or disposer) is required, in addition to the other documents listed here.