Shop around. It may sound obvious, but car rental companies' rates can vary widely for the same car category, depending on when and where you book. Check several different locations in the area where you need the car and several car rental companies.
If you are flying to your location, keep in mind some airports charge additional taxes for on-site car rental agencies, so you may find a better deal in a neighboring town.
Travel websites that aggregate results for numerous car rental companies may be a useful tool to help you shop around. In addition, see if you qualify for additional discounts or special rates through organizations such as AAA or AARP.
Get the cheapest car that meets your needs. A car rental company will automatically upgrade customers to the next size class of car if it runs out of cars in the category you book, so you may find yourself in a larger car than you originally booked at no extra charge. It's also relatively common to find free upgrade coupons online or by joining the car rental agency's mailing list or frequent customer program. Using these strategies will allow you to drive a larger, more expensive rental car at a lower cost.
Choose extra insurance carefully. It's standard practice for car rental companies to offer customers their added car insurance, but it may or may not be necessary, depending on your auto insurance coverage. Read "Buy car rental coverage in auto insurance?" for an overview of whether you need coverage, then check with your car insurance agent about what your car insurance policy covers for car rentals to see if it's necessary to take the rental car company's insurance.
Fill up wisely. If you forget to return your rental car with the same amount of fuel that was in the tank when you picked it up, the car rental agency will probably add an exorbitant per-gallon cost for replenishing the gas. Make sure you fill the tank to the noted level before you return it. You also can use a gas app, such as GasBuddy, Cost2Drive or the Yellow Pages gas function to check for gas prices in the area where you are traveling. It's difficult to determine a good-price estimate in an unfamiliar town.
Don't be late. Pay attention to the time you agreed to return your rental car on your contract, and take care not to arrive late. Companies usually charge penalties for returning car rentals late. They're counting on your arrival to prep the car and rent it to the next person. If you do end up running late, even just a bit, call the rental agency and make sure they make a note on your account. While you'll still pay for the extra time you had the car, you will most likely be able to avoid any penalties.
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