Feel constrained by the flight schedules of commercial airlines? Tired of paying high prices to get to those hard-to-reach places?

Well, here's an idea: Try looking for a used airplane.But while you may want to kick the tires, don't expect the experience to be a buyer's market: The demand is intense, the supply short and the market for small used airplanes is hot.

One popular small 13-year-old jet that sold for $650,000 a year ago is worth a cool $850,000 today. Industry sources say prices for the most popular planes have climbed 20 to 30 percent during the past two years.

Part of the reason is the rise of the corporate jet: Many businesses are logging more hours in the air _ and consequently are trying to trade up to bigger or faster aircraft.

Foreign customers are also a factor: For many, the decline of the dollar makes the U.S. used airplane market an attractive place to shop.

"Buyers are having to look harder and pay more," said Cosby Stone, publisher of Trade-A-Plane, a 170-page tabloid published in Crossville, Tenn., that advertises used aircraft to 210,000 readers worldwide every 10 days.

And the used airplane market is expected to stay strong, industry spokesmen predict, because demand will remain constant and the supply won't increase.

That's partly because new airplane production has dropped dramatically, principally because of product liability costs. Shopping for a used airplane is not like "going down to a used-car lot and having a whole smorgasbord to choose from," said Bob Minter of Nashville, Tenn..

In fact, buyers may need to mount a national search to buy a used plane. Even then, they may well find only a few models available, dealers said.