Most important, when shopping for the best deal, base your cost comparison on the final costs, not the advertised base rate. Once all the extra, non-optional charges are factored-in, the best deal may actually have had a higher base rental rate. Rental franchises are quite clever at tacking-on extra charges, making them sound as if they're taxes, when in fact they're not. Thus, you'll see mysterious charges such as "Concession recovery fee" or "Customer Facility Charge","Vehicle License Recoupment Fee", which translate to "our lease costs of our location","the cost of our infrastructure","our license plate cost", respectively. These bogus charges are arbitrary and will vary greatly from one franchiser to the next, adding as much as 15 per cent or more to your bill, not including the real taxes that will go on top of all this. What this means in real terms is that an advertised rate of 30 dollars a day is really 35 dollars before taxes. Such costs, in a normal world, should be included in the base rate, but unfortunately the car rental industry as a whole is guilty of this dishonest behavior and I'm afraid is does work at making people believe they're paying less.

Don't go for the pre-paid tank of gas deal. You're not very likely to return the car completely empty and no matter what price per gallon/liter they quote, it's their win. The inconvenience of refilling the tank before returning the car is a very small thing!

Don't let them pressure you into buying optional features, such as insurance. Liability insurance is more than likely not necessary as your own policy probably already covers you. For example if you're a Canadian or US driver and you're renting in either country, your driver's liability insurance takes care of you. Some credit and debit cards also include such coverage. Furthermore, the high priced option likely comes with a big deductible. Life insurance is just money thrown out the window.

The loss/damage waiver (LDW) isn't insurance. The car they rent to you is covered by the their own insurance already, and the LDW is just a treaty between you and the franchisor whereby they absolve you of any responsibility if the vehicle is damaged. The problem is that the price of this option often exceeds the rental rate. LDW is a very important source of profit for rental companies, and they're quite eager to sell it to you. The usual recommendation is to decline the LDW, especially since your own insurance may already cover you for damage to rental vehicles.

Rental car franchises also inclined to charge a weekly rate for what is really a 5 day rental. While sometimes the weekly rate might be a better deal than paying a daily rate for five days, verify first that that's actually the case. Verify that those bogus extra charges mentioned earlier as well as any other daily charges aren't also charged for 7 days instead of 5.

Book via the Internet for the best rates. Competition amongst the car rental companies is most fierce on the Internet and there's no easier way to compare rates. Pay attention to the specials or "deals" on offer.

Most rental car franchises in the USA accept debit cards with the Master Card or Visa logo, instead of credit cards. However, few accept them in Canada and there are areas of the USA where almost no rental companies will accept them, such as in New_York City. If you reserve a vehicle, make sure to verify that they indeed accept your debit card, or you might have an embarrassing moment once you get there. Some states prohibit rental car companies from refusing debit cards. Such is the case with New York state, apparently NYC being exempt from that law.

Review the rental agreement carefully before signing it. Some unscrupulous franchisers are known to add-on rental options without asking if you actually want them. One even had me down for life insurance, as if that had anything to do with renting a car!

Now, a dirty little trick of your own: Always book "economy" cars, thus guaranteeing the lowest rate possible. If you book well in advance, it's most likely that they won't have any economy vehicles on the lot when you get there, and you'll be upgraded to a compact, mid-size car or even a van at no extra charge. If you didn't really want the economy car and they have one, then just change your mind on the spot and upgrade, although in this case you will pay a higher rate. In the long run, you'll save a fortune, even if you're being a bit dishonest in the process!

Some rental companies allow you to drop-off the vehicle at a different location within the same state at no extra charge. For example, I recently picked-up a vehicle from National rent-a-car at Westchester County airport and dropped it off at John F Kennedy airport at no extra cost. Normally, you would have to pick-up the vehicle at the same place as you drop it off, and in the case of JFK, that would have meant a much higher rental cost.

Tom Germain is a Canadian who in 2001 decided he wasn't going to put up with any more winters and moved to Mexico. He never looked back and moved around the world every couple years, making his home in Argentina, the Canary Islands, Mauritius, and now Colombia. In his 2 blogs, Permatourist ( http://www.permatourist.com ) and Ocolombia ( http://www.ocolombia.com ) he tells of his experiences and offers invaluable tips on how you can live the life of a "permatourist".