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."