Shop around for the best rates. Compare all fees, in addition to the daily/weekly rate, before renting. Most car rental contracts make the consumer liable for all damage to the vehicle, no matter who caused it. Before buying a rental company's collision or loss damage waiver, check with your own car insurance company and your credit card company to see if they cover car rentals and to what extent. It pays to do your homework because these policies can add $3 to $15 per day to your rental charges. Rental companies also might sell loss of use and liability insurance. Check with your insurance agent in advance, so you do not duplicate coverage you already have. If you pay by credit card, some rental companies will place a hold or freeze on your account during the rental period. Others might start to charge your account before the rental period is over. Find out the companies policy in advance. Carefully inspect the vehicle and its tires before renting and write down all scratches and dents you see. Check refueling policies. You can refill at a local gas station, you can let the car rental company refuel the vehicle at its price, or you can pay in advance for a refill which will cost you needlessly if there is any unused gas when you return the vehicle.