An Illinois motor vehicle bill of sale documents the purchase and sale of a motor vehicle between a private seller and buyer in the State of Illinois. To download a free Car Sale Agreement template, click the button below.An Illinois motor vehicle bill of sale legally transfers ownership of a car or other motor vehicle in the state of Illinois. Filling out this Bill of Sale is straightforward. Motor Vehicle (DMV) Bill of Sale Form Affirms the information contained in a transaction of a vehicle for a payment amount. Complete and mail the Notice of Sale form. (attached to the bottom of the title) to the. A vehicle private sales receipt serves as formal documentation provided to a buyer as evidence of payment for purchasing a car from a private seller. Under the Uniform Commercial Code, words can be added to limit the seller's warranty in a transaction. Example. Once the required information is written, the contract is finalized with both parties' signatures.