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. A bill of sale is a legal document that contains all the details of sale between the buyer and the seller. For example, in the case of the purchase of a used vehicle, provincial legislation often requires a bill of sale to register the vehicle to the new owner. To register a vehicle you have bought privately in manitoba, you’ll need the following: 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.