□ Not included with the vehicle sale. A Utah motor vehicle bill of sale, known as Form TC-843, is an official document that provides proof that a vehicle has been sold in the State of Utah.Motor Vehicle Bill of Sale (Form TC-843)– Can be used to prove the sale and purchase of either a motorcycle or automobile in the state of Utah. A Utah motor vehicle bill of sale is written documentation of a transfer of vehicle ownership. Create a Utah bill of sale form to document the transfer of ownership of a vehicle or another piece of personal property. Utah State Tax Commission. This form will cover your registration as well.