When one Saudi prince decided to ditch his old turboprop and upgrade to his first jet, he called aviation consultant Ken Hoffman and presented him with the challenge: One business jet for $1 million.

That's not a lot of cash in a market where a new, unfurbished Boeing Business Jet goes for $57 million. But Hoffman managed to find a shiny, fully equipped Cessna Citation 501. It had simply changed hands a few times.

Private jets have long been the preferred ride of Americans with big bucks, but with the economies of India, Russia, and China smoking hot, the well-heeled here had to line up for corporate carriages. "For the last two years, well over 50 percent of all new corporate aircraft manufactured have been sold outside the U.S.," says Jay Duckson, president of aircraft broker Central Business Jets. "Prior to that, nearly 80 percent of all new aircraft were being delivered within the boundaries of North America. That's an enormous swing."

Even despite the recent market turmoil, demand remains incredibly strong—so much so that manufacturers like Cessna, Gulfstream, Bombardier, Dassault Falcon, and Hawker haven't been able to crank out planes fast enough. New private-airplane deliveries in 2001 hit a record 784 units; by 2007 that number reached 1,138. With business jets in such high demand, buyers haven't been able to get what they want when they want it—even if they're from the Saudi royal family.

"It depends on the model," says Doug Oliver, director of corporate communications for Cessna. "Our new CJ4 is sold out for the first five or six years. To get in line for another airplane will be at least a year's wait."

For a Citation, the wait is three to four years. Dan Holenger, sales associate and market analyst for Clay Lacy Aviation, a used-jet broker in Seattle, says, "Some people out there can't wait that long." One approach: tThey'll buy someone else's position in line for between $3 million and $8 million, depending on demand. "Foreign buyers see that premium as chump change," he says. "They are aggressive, and they will spend what they need to get an aircraft."

Or, like the anonymous prince—or maybe someone with deep pockets looking to be less indulgent—they will buy used. Airplanes, after all, don't wear out like cars; in fact, they hold their value relatively well. A brand-new Citation Excel, which carries seven to 10 passengers and has a 2,600-nautical-mile range, costs nearly $14 million, while a pre-owned Excel can sell for between $7 million and $9 million.

"Like a fiberglass boat," Duckson says, "the airframe itself generally doesn't wear out until 50 years or 30,000 flight hours, so it's not as if it's an automobile where in seven to 10 years you're on borrowed time."

Likewise, last year the median price for a used Challenger 604, capable of carrying nine to 19 passengers up to 4,077 nautical miles, fell between $23 million and $26 million, according to Holenger. Its descendant, the Challenger 605 (the company stopped production on the 604), costs $30 million, and someone placing an order today will have to wait until 2012 for delivery.  

"Of course, you're buying what someone else liked in the pre-owned market," Duckson adds. Completion centers can strip and replace an old interior in three to four months, but usually after a two- to three-month wait. Still, that's six months compared with four years.

The prince's 1977 jet was owned briefly by Russ Meyer, C.E.O. of Cessna, then purchased by Ralph Kiewit, C.E.O. of a California construction firm, who flew it for 30 years. On top of the purchase price, the prince spent $200,000 updating the instruments and electronics, adding a collision-avoidance system, an updated, more precise version of G.P.S. known as W.A.A.S. (Wide Area Augmentation System), "and a little repair to the crew seat where it had worn through," Hoffman says. The plane was delivered in June, just a couple of months after it had been purchased.

Phil Jordan, chairman of the National Aircraft Resale Association, says the resale market for jets built before 2000 is sluggish due largely to the noisy, fuel-sucking power plants built during the last century. "With fuel prices getting higher, newer engines burn 20 to 60 percent less fuel," Jordan says. Europe also has stringent noise restrictions, which means that the owner of an old business jet would have to land at a major metropolitan airport and drive to their villa in Tuscany.  

Buyers, however, can add "hush kits" on the engines to lower the decibel level. It's also possible to install newer, quieter, fuel-sipping engine models, but that may present a problem with government certification. When a business jet rolls off the assembly line, it comes certified with a particular engine model. A different engine usually requires that the airplane undergo recertification, and for that the manufacturer must supply engineering data.

"The problem is you have to get the manufacturer to support you on that," says Jordan. "That's counterproductive to them selling a new airplane."

Not so fast. In fact, Cessna's getting into the act with its new Value Plus program. "We refurb the airplane completely—new paint, new interior, do maintenance, and it comes with a warranty," says Oliver. "You can get in a used—Value Plus—airplane very quickly. Probably right now."