Figuring out what a decent price for a rental car is versus a complete rip-off is not nearly as easy to determine as one might initially think. Rates vary depending on which company, which city, and which day it is. Strangely enough, it is not unheard of to get four different quotes on how much it would cost to rent a car on four consecutive days. One of the things that kills car renters' wallets, is not doing the research to learn what the local fees and taxes on car rentals are.

In fact, local and state taxes make up an extremely high amount of the total car rental cost. In the 100 most heavily trafficked U.S. airports, the airport itself, and demanded rent was often a problem. Such add-ons averaged nearly 26 percent of the entire cost, compared with a 14 percent average for off-airport locations. In some cities the gap between on-airport and off-airport costs is nearly unbelievable. In Dallas, for example, 61.4 percent of the total cost of renting a car at the airport came from taxes, while taxes at nearby neighborhood locations only made up 17 percent of the total. Like most taxes, these just continue to grow.

The most expensive cities in the United States to rent a car (the taxes are so high that it actually is an absurd idea for most people to even think about renting a vehicle here) are Boston, New York, and Houston. In all three cities rates can easily almost double over what was advertised. At Houston's Intercontinental Airport, if you rent a car for two days at $50 per day, you'd expect your bill to be about $100. Once taxes and fees are added in, watch out, because you will owe a minimum of $171. Aside from the big three, some of the other worst rental rates from airports include Austin, Cleveland, Dallas/Fort Worth and New Orleans. No matter what city you are in, it is often a good idea to rent from centers away from the airport. They will always be cheaper.

Taxes and fees (which are often much higher in cities that need funds for construction of convention centers or stadiums) can increase your final bill by up to 70 percent. Watch out for these cities, watch out for the taxes. While it may be uavoidable, really weigh your options. Is it really worth this much to rent a car instead of using public transportation? At the very least, find a rental center away from the airport. It might be a little inconvienent, but at least you save yourself something, which in high tax cities, migh end up being more than just a few pennies; it might be a small bundle.