If you need to return your car rental to Stuttgart Echterdingen Airport, you can drive back to the rental car center. Follow signs for car rental return and move in that direction. Most companies for car rentals in Stuttgart Echterdingen are open 24 hours a day so that you can return the rental car at any time. Some rental companies have a full-on full policy where you get and return your rental car with a full gas tank. Depending on your agreement, make sure the gas tank is at the state of the expected amount. There are rental companies that will charge up to three times the normal amount, so remember to honor the rental company's contract.