County of Harris. §. This is to certify that on the.Next, provide the vehicle details, including make, model, and VIN. Bill of Sale to a Motor Vehicle. MV-028. Use this car purchase agreement template to customize the financing information for your car along with other required details. Vehicles are required to be titled in the buyer's name within 30 days from the date of sale. Adhere to this straightforward guide to edit Bill of Sale to a Motor Vehicle - Harris County Tax Office in PDF format online free of charge. No information is available for this page.