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. Complete and mail the Notice of Sale form.(attached to the bottom of the title) to the. ACCEPTANCE DATE: ("Acceptance Date"). SELLER'S INFORMATION: Seller's Signature: Seller's Name (print):. Both the seller and buyer of a vehicle are required to fill out a Car Sale Agreement to ensure a clear, legal, and mutually agreed-upon transaction. An Illinois motor vehicle bill of sale legally transfers ownership of a car or other motor vehicle in the state of Illinois. You are required to submit either payment of tax or proof that no tax is due before your vehicle can be titled. A good option to get in the car business is with a wholesale dealer license. Real estate wholesaling involves finding properties for sale, putting them under contract and then finding a thirdparty buyer.