At a self service station, make sure the pump starts at zero and the price being charged agrees with the price advertised on the signs in the station. A good way to check this is to stop the pump at one gallon and compare the prices.At full service stations, be sure to check all of the above and also make sure you are getting the grade of gasoline you asked for; if you asked for regular, make sure they’re not giving you premium at a higher price. When the sale is done, make sure the amount you pay the attendant agrees with the amount shown on the pump.