Renting a car during your travels can sometimes be a big headache. Even travel professionals often have trouble sorting out how the rental car companies figure pricing, fuel, surcharges, and insurance.

Never fear! This is your chance to learn something about the mysterious car rental industry BEFORE you walk up to the counter and get your keys.

First, you should know that Enterprise consistently ranks highest in customer satisfaction according to the J.D. Power and Associates 2007 Rental Car Satisfaction Study. Hertz and National were next on the list.

On the downside, though, customers have an average wait of over 21 minutes to get their car from a rental company, which can be frustrating for many people. Also, the cost of renting a car is going up as Ford and General Motors downsize their operations and produce more expensive cars, leaving fewer generic models for rental companies to buy. More expensive cars means more expensive rental prices, too.

The costs don’t stop there, of course. When you rent a car, you’ll notice many taxes and fees on the bill. Often, these taxes and fees aren’t included in the initial rental quote. Make sure you ask what the final price will be so that the extra costs won’t be an unpleasant surprise.

Here are some of the fees and taxes you might encounter:

Additional drivers fee: If anyone but the renter drives the car, the company will charge $3 to $25 per additional driver. Check your company’s policies before you rent. Some companies don’t charge for a spouse, and other companies have policies that vary by location.

Airport concession fees: It costs money for the rental car companies to rent space at the airport, and this cost is passed along to you at up to 10 percent of the base rate. If you can, avoid renting from airports and go to a neighboring location instead.

Convention center/sports arena/stadium tax: You are helping to build the area’s shiny new complex, whether you want to or not. For example, both Boston and Los Angeles charge a $10 per day stadium tax within the city limits.

Deposit: Rental car agencies will place a charge on your credit card as a deposit on the vehicle when you take possession of it. They won’t actually process the charge unless you bring the car back damaged, though. Be sure to check the car completely when you pick it up AND when you return it to make sure there is no damage, inside or out, if you don’t want the deposit to become permanent.

Drop-off fee: If you return the car to a different place than where you rented it in the same city, you might have to pay this fee. This may also include “one-way” rentals in which you drop the car off in an entirely different city from where you rented it. These fees can run into the hundreds of dollars, so check before you book. Hertz doesn’t charge one-way or drop-off fees anymore, National doesn’t charge drop-off fees, and Enterprise allows one-way rentals in Florida, Texas and California.

Equipment rental fee: Need a car seat or ski rack? It’ll cost you. Even GPS units and cell phones can be rented, but everything has a price.

Frequent-flier tax: This is a recent, mostly hidden fee. It’s a charge you pay when you earn frequent-flier miles for your rental. The fee tends to be 7.5 percent of the value of the miles you earn.

Fuel charge: If you bring back the car without a full tank of gas, you’ll pay for the missing fuel. The rental car companies will charge much more than you pay at the pump, so try to make sure the car is full before you return it or take the pre-pay option. Make sure it’s full when you LEAVE the rental car lot, too; you don’t want to pay for gas that they should have given you in the first place. Some good news: Hertz has taken action against fuel gouging and instead of charging up to $8 a gallon to refill the tank, will charge you a flat $6.99 fee plus the market price for the fuel.

Late fee: Rental car companies work on a 24-hour cycle. If you pick your car up at noon, return it before noon on the final day or be charged a fee for your tardiness. The late fee is usually charged by the hour until it gets so high that the company simply charges the daily rental rate. Some companies (but not ALL of them) have a grace period of 30 to 59 minutes for returning the car late, so check with your company if you want to know their policy.

Mileage fee: Some rental cars have unlimited mileage, so you can drive as much as you like without worrying about anything but the gas. But when your car doesn’t have unlimited mileage, you’ll pay a per-mile fee for either the miles you drive overall or the miles you drive over the number of miles they allow you.

Out-of-state fee: Some rental car companies charge you if you drive the vehicle across state lines, so check with your company before you book.

Parking tax: Companies charge this fee to pay for the cost of renting their own parking lot. The fee is usually about 30 cents.

Peak season surcharge: The law of supply and demand in action. If it’s a popular time, some rental car companies will up their prices accordingly.

Reimbursement fee/vehicle license fee/vehicle excise tax: This covers what the rental car company spends to register and title the car. It’s usually around 3 to 8 percent of the base rental rate.

State and local sales tax: This varies by state and locality, obviously.

Young drivers fee: It may not seem fair to you, but it’s perfectly fair to the rental car companies. If you’re younger than 25, expect to pay more per day to rent a car. The increased cost may be as little as $10 per day or as much as $80 per day, depending on the company you choose.

So what can you do to minimize your car rental costs? Here are some tips:

Many car-rental companies are offering free upgrades to gas-guzzling sedans and SUVs. Car-rental companies are struggling to keep up with the demand for more fuel-efficient vehicles so don’t be fooled into taking a “better” deal if you chose a smaller car in the first place.

• Rent on Saturdays. Many cars booked for the weekend are not picked up on Saturdays, so the rental agencies might have a surplus.
• Avoid calling the 800 number. Call the direct number of the office from which you’re trying to rent, since they’ll probably have more negotiating leeway than a national call center.
• Check back. Car rental prices can change a dozen times a day, based on demand. Check online, but also call the agency to speak to a person. Agents might be able to drop the rate for you, but you have to ask.
• Take photos before you drive the car off the rental lot. Take pictures of any dings and dents before you take possession of the car and show the pictures to the rental agent so that you have proof that any damage was already there.

With some advance planning and effort, you can avoid getting too stressed about the process of renting a car. The Complete Travel Detective Bible has still more tips for getting the most out of your rental car (and understanding the costs), so check it out at your local bookstore or click here.

By Erica Adams for PeterGreenberg.com.

Check out more excerpts from Peter’s Travel Detective Bible.

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