The left front wheel was out of alignment. It shimmied at high speeds. The steering wheel vibrated. We were tempted to return the 2003 Ford Focus SE sedan to the airport Hertz fleet.

But we looked at the odometer. This rental car had been driven 25,000 miles before we picked it up. Later, we checked its vehicle identification number and manufacture date. Judging from that information, the Focus had been in service a bit more than five months. That worked out to an average 5,000 miles per month, which meant the Focus was going to auction.

Good car-rental companies don't keep high-mileage cars. They ship them for resale. Hertz is a good car-rental company. Our high-mileage 2003 car was a traveler. It came to the New Orleans fleet from Texas, which is why it was still hanging around when we arrived.

We decided to keep the car, partly because I told my traveling partner, Martha McNeil Hamilton, that driving a hard-driven "new" car would make a good column. We had lots of running around to do on our book tour in New Orleans and New Iberia, my late mother's Louisiana hometown, about 130 miles west of here.

"Let's see how it holds up," I suggested. Martha said "Hmph," by which I assumed she meant "Yes."

It was a revealing experience, quite different from driving the factory-fresh vehicles that usually grace this column. It offered an insight into the way rental companies think, which is not the way many individual car buyers think.

That's because car-rental companies don't sell cars. They sell fantasy, convenience. To them, a car is a mobile extension of your hotel. So the rental companies do what Hertz did with our Focus SE sedan. They order it with the base engine: a 2-liter inline four-cylinder Zetec that produces 110 horsepower. They order the four-speed automatic transmission (called the "transaxle" in front-wheel-drive cars such as the Focus) because most rental customers in the United States don't want manual gearboxes.

There's something else. The rental companies assume that budget-minded customers who ask for small cars aren't interested in performance and handling. So rental companies order base suspension systems to go with the base engines.

But the rental companies also assume that budget-minded customers would be delighted to have an economy car with lots of luxury touches, which is why our Focus came with power windows and locks, a power-operated trunk lid, a good audio system, and the "upscale" velour-covered seats that Ford thinks are more appealing to older buyers. (In the Focus, Ford offers "sporty woven seat materials . . . aimed at younger buyers," according to its product summaries.) Anyway, the cosmetic stuff had a soothing effect. It all worked properly, too, and Hertz did an excellent job of presenting a car with a commendably clean, fresh-smelling interior. Hertz has apparently started putting no-smoking signs in some of its cars, as there was one in our Focus. Good idea.

The shimmy came and went, as often is the case with such disorders. Luckily, in our case, it went more than it came. But in driving around New Orleans and environs, we quickly surmised where that shimmy might have come from. The city's streets are absolutely awful, even worse than those in the District of Columbia, which I thought was impossible before I returned here, to my hometown.

Still, even with that intermittent left-wheel problem, the Focus SE sedan turned out to be a delight. It handled extremely well in panic highway maneuvers. Overall ride comfort was good, although the seats could use a bit more work in that area. That little 110-horsepower engine turned out to be more gutsy than wimpy, certainly for regional travel. The sedan's trunk, measuring 12.9 cubic feet, was big enough to carry two suitcases and an assortment of personal and computer bags.

Frankly, anybody in the market r a truly cheap ride should track down this one, or one like it, at a car auction. Hertz says it will fix the left front wheel's alignment problem.