All vehicle registration and title transfers require proof of insurance and a current vehicle inspection that is no more than 90 days old. The Bexar County Tax Office offers the option of paying your Property Taxes online with either a major credit card or an electronic check (eCheck).You state the agreed upon sale price, and the amount of down payment. I get this query all the time from people when selling cars. Will I write up the bill of sale for less money so they can avoid taxes. Any person buying or accepting a car in New York must: Sign the bill of sale; Pay sales tax or present proof of exemption; Register and title the vehicle. The tax is a debt of the purchaser until paid to the dealer. The dealer will remit the tax to the county tax assessor-collector.