If you're in your early 20s, you've probably already learned that the biggest U.S. rental car companies don't want your business. The safety record of drivers under 25 is just too risky, those companies say, and so in most of the U.S. and several European countries, major companies either turn away travelers in their early 20s or make them pay extra.
But few travelers realize that if you're retired and traveling in Mexico or Europe, you could run into the same problem.
The most troubling way to learn this is probably the way that Barbara Pritzkat of Redondo Beach did. Last fall, Pritzkat visited England and France, relying on her travel agent to arrange rental cars in both countries. In Paris, her arrangements through Auto Europe went flawlessly. But when she showed up at the counter of Europcar, an Auto Europe partner in Manchester, England, and produced her driver's license, they turned her down.
"You're 71 years old," she was told. "We don't rent to drivers over 69."
"I need not embroider the scene," Pritzkat wrote dryly in a recent letter to The Times.
Her luck did improve. At an Alamo office next door, representatives rented a car to her without hesitation and made several long-distance calls to keep her from paying extra for her Europcar misadventure.
An alert travel agent or rental-car booking agent probably could have prevented that situation, industry veterans agree. Pritzkat came home wiser, and travelers and travel agents should heed the same lesson: Though none of the biggest rental-car companies have maximum age limits for cars in the United States or Canada (except for Budget, where maximum ages vary by location in Canada), many of those companies' outlets in Europe and Mexico use age limits that exclude travelers young and old.
To avoid surprises, no matter which rental company you use or what nation you're headed for, it's wise to ask up front about age limits for drivers. Especially if you're under 30 with expensive tastes, or over 69 and headed for Mexico or Ireland, beware.
Industry veterans say companies usually set the maxiumum age, as they do the minimum, in response to government restrictions and to premiums they are charged by insurers. These are not new limits, but as many industry veterans acknowledge, they often are overlooked.
Here's a quick sampling of rental-car age policies in Mexico and Europe. In most destinations favored by American tourists, most rental car companies have no maximum ages. But here are exceptions:
* In Mexico: Budget (telephone  527-0700) won't rent to anyone 71 or older. Avis (tel.  331-1212) won't rent to anyone 70 or over. Alamo (tel.  327-9633) won't rent to anyone 66 or older. Hertz, meanwhile, has no maximum limit (tel.  654-3131).
* In Britain: Budget won't rent to anyone 71 or older. Europcar rentals through Auto Europe won't rent to anyone 70 or older. Until last year, Alamo wouldn't rent to anyone over 75, but last June Alamo did away with that limit.
* In Ireland: Hertz and Budget will rent to 75-year-olds, but no one older. Avis won't rent to 75-year-olds, will rent some models of cars to 74-year-olds, but drops its maximum allowable age to 65 on other models. Alamo won't rent to anyone 75 or over. If you're 75 or older, you can't rent a Europcar through Auto Europe (tel.  223-5555). But if you're between 70 and 75, there's room for negotiation: Some outlets won't rent to you, but others will trust you with an automatic transmission if you pay an extra $18 per day.
* In Italy: Budget won't rent to anyone 76 or older.
* In Portugal: Alamo won't rent to anyone over 65. (And on the Portuguese island of Madeira, Hertz won't rent to anyone over 75.)
* In the Netherlands: Budget won't rent to anyone 76 or older.
* In Egypt and the Philippines: Budget won't rent to anyone 66 or older.
Another key to sorting out restrictions in Europe is understanding the role of Auto Europe, a company used by many major travel agencies.
Unlike such companies as Hertz and Avis that deal only with their own company's outlets across the Atlantic, Auto Europe is a U.S.-based reservation service that acts as American representative for several large and small rental-car suppliers throughout Europe, including Europcar, Alamo and Avis. This setup allows Auto Europe's customers to reserve cars in multiple countries from multiple sources with a single call.
But consumers and travel agents need to remember (and Auto Europe's booking representatives should point out) that different rental-car suppliers under the Auto Europe umbrella sometimes have different age-limit policies. In fact, sometimes there's one age limit for drivers renting directly from the supplier and another age limit for drivers who book through Auto Europe.
"It's something you want to bring up with your travel agent," says Nanci DeRedin, Auto Europe vice president of advertising and marketing. DeRedin also pointed out an upside to mentioning the driver's age when making a reservation: In many cases, senior discounts are available.
At the American Assn. of Retired Persons, spokesman Tom Otwell says the organization opposes maximum-age limits in the U.S. but adds that "there's not much AARP can do" about practices abroad. The best strategy for a retired American renting abroad, Otwell says, is to "shop around, or try to use a travel agent to intercede on your behalf."
Reynolds travels anonymously at the newspaper's expense, accepting no special discounts or subsidized trips. He welcomes comments and suggestions, but cannot respond individually to letters and calls. Write Travel Insider, Los Angeles Times, Times Mirror Square, Los Angeles 90053 or e-mail firstname.lastname@example.org.