Hiring a car can really grant you flexibility and independence on a trip and sometimes it is the only way to move around. But it can be incredibly frustrating - from finding the best deal, figuring out which options you'll need and reading small print about all hidden fees.
Decide on a vehicle
You'll need to be careful when choosing a vehicle. Based on if you are vacationing with children or with lots of luggage, you should hire a SUV or a large sedan. If you want the best price, you should hire smallest model available. Additionally, there are other factors like environmental friendliness, manual or automatic transmission and optional accessories such as GPS or child seat.
Book your car
In case you are renting for less than 7 days, you'll usually be better with big rental companies like Hertz, Avis, Dollar, Budget,... If you are renting for over a week, it usually is better to book with local companies or auto dealers.
It is usually smart to perform a thorough research. You can start on the web by using holiday search engines (for example Expedia) to get an overall feeling about the rates you will be thinking about. After that check out car rental companies' websites and compare them to those found by travel search engines. Often it will be cheaper given that companies tend to provide exclusive deals and offers right at their web sites. Then of course you'll want to do a quick search on discount codes and promotional codes to even lower hire price.
Finding true, final price can sometimes be very difficult or even impossible. That is because rental companies or search engines don't want to show you or simply just do not have details about state and local fees, insurance, extra driver fees, airport taxes, drop off charges,... The price you were displayed while searching and the one you pay can therefore be very different! Your best option is usually to make a booking by using a company/website which includes "No Hidden Fees / Final Price" policy. Also be careful when booking because prices can change from minute to minute. Unless you book immediately, you'll never be sure you'll get the same price when you return later for booking.
Returning the car
Unless stated otherwise, car hire companies are expecting that you return your car in condition it was when you picked it up at arrival. This means full tank and no damage in any way. Always fill the tank your self ahead of returning. If they get it done for you, you will usually pay far more for same amount of fuel as compared to at gas station.
Return car promptly. If you are overdue, some companies will charge you extra. In some cases you might have to pay more if you return the car ahead of time (yes, it sounds ridiculous but early return fee can sometimes be charged)!