There are several Fuel policy options when renting a car in Yellowstone Budget: "Full-to-Full". This is the most advantageous and transparent policy. You receive the car with a full tank and must return it with the same level of fuel. In this case, you will need to find a gas station near the vehicle return location, as if the tank is not filled upon return, an additional fuel fee is charged, and possibly an additional service fee. "Same-to-Same". This is a rarer policy. In this case, you receive the car with a partially filled tank and return it with the same level.