Rental car revelations

Experienced travelers realize that renting a car requires having a valid driver's license and credit card. Are you also aware that there are age limits, both upper (generally 75 years) and lower (generally 21 years) for renting a car, that some companies check your driving record before they'll let you have one of their vehicles, or that when you give a rental company your credit card as a deposit, they actually freeze a portion of your account's credit reserve, often for more than the total amount of the bill?

Too often, however, the biggest rental car surprise is the final bill. Here's a compendium of rental basics to help you avoid any unpleasant shocks.

Rental rates, of course, are the biggest cost factor. In general, drivers have two basic car rental options -- daily rates and longer term plans with free mileage. Daily charges are calculated on a 24-hour period, with extra fees if you return the car later than a one-hour grace period. Weekend plans generally run from noon Thursday to noon Monday. Also know that if you rent a car by the week and bring it back early, you may be charged the higher daily rates. If you return the car to another location, significant drop-off charges may be imposed.

When it comes to actually setting rates, most auto rental companies use yield management techniques similar to airlines and hotels, though since they seldom require travelers to lock in reservations with a credit card, their systems are somewhat easier to negotiate.

The Internet has greatly simplified the process of obtaining rental rates and reservations, but good old-fashioned phone calls still work well. In general, it pays to shop around, especially if you're doing it online, because the major companies are currently offering 20 percent discounts to those who book directly from their sites. Make reservations as far in advance as possible, but since prices can and do fluctuate with market demand, it can also pay handsomely to check back from time to time and see if you can snag a better rate. Often, the best rates are posted only a day or two in advance.

Also, consider renting a car from agencies not located in airport terminals. Since they don't have to pay the airport surcharges, their fees are often as much as 30 percent less than the on-site majors.

Renting a car in another country can involve a confusion of different currencies, taxes and regulations. To further complicate the situation, rental rates vary between countries, seasons, companies, even different locations in the same city. Hertz, Avis, National and Budget all maintain international reservation systems that reduce the paperwork, but at a premium price.

Local companies also rent cars with rates that are often a third less than the multi-nationals. The same money saving-strategies that work at home often apply overseas, although foreign rental companies seldom volunteer information; you have to ask.

If you plan to have the car four days or less, daily rates will probably be the cheapest. Lease plans are often the best deal for rentals of a month or more. Here's another foreign factor -- cars with standard transmissions offer the lowest rates; you'll pay extra for an automatic transmission.

If you plan to pick up the car in one country and drop it off in another, ask about extra charges for one-way rentals. Most companies have them; some are enormous.

Insurance is another big cost factor. Buying unnecessary coverage can double your costs, but declining needed insurance can lead to a major financial headache.

If you're renting a car in the United States and Canada and are covered by home or auto insurance, you may already be protected. Overseas rentals are another issue entirely, and few insurance companies automatically provide foreign coverage. Many companies have lowered their protection for domestically rented vehicles. If necessary, buy a liability supplement to pay for injuries and damages to others.

Collision-damage insurance, which pays for damage to the rented vehicle, runs $10 to $20 a day, but can be much higher in nations like Italy. But be aware that this coverage can be voided if the driver travels on roads that are unpaved or considered particularly dangerous. Other policies cover any insurance deductibles you might incur. Figured on a yearly basis, this protection is exorbitant, especially if you're already covered by your own policy. On the other hand, if you're not covered, extra protection is essential.

Personal-accident coverage is another kind of insurance that can add $2 to $5 a day to the bill. It insures you against accidental death and assists with medical expenses. But your own life or health insurance may already provide better coverage at a much lower cost. And personal effects insurance, which safeguards your luggage, may be a total waste if your homeowner's policy covers you when you're away.

So, as a general rule before you leave home, find out if your personal or business auto insurance will protect you where you're going. If you're not covered, buy yourself financial peace of mind.

Taxes are another huge and often overlooked rental car line item. Many countries, states, cities and even airports tack on daily charges that can add up fast. France, for example, can jack up the final bill by 25 percent, which means travelers can save money by picking up the car in a neighboring country like Luxembourg that has lower tax rates.

Other fees can also find their way on to the bill, from daily charges for extra drivers to rental of auxiliary equipment, such as ski racks, car seats and boat tows. Also remember that rental rates never include the cost of gas, so fill the tank before returning the car. Rental company prices can be twice as fuelish as nearby pumps, which at today's prices adds up to a hefty investment.

The best way to avoid nasty check-in surprises? Always ask for an estimated final bill when you rent the car. That's also the best time to question any charges you don't understand.