Trying to work out whether to go with full/empty policy of full /full on car hire, the former is clearly a ruse that benefits the renatl company . Key seems to be how big the premium is on the fuel you have to prepay for on the full empty policy. Looking at a Fiat Panda which hold 8 gallons with a cost of about £48 to fill the tank if buying from a local petrol station. Anyone know what the mark up on that will be at a rental agency doing a full/empty fuel policy. Will it be double, more than double ? Recent experience would be great.