Currently, approximately 10 percent of the worldwide fleet of private aircraft is for sale. That serves to keep prices down; however, the projected decrease in new private jet deliveries could bring an uptick in transaction prices on preowned aircraft, particularly over the next 2-3 years. Aviation consultants and industry professionals have also reported seeing a recent rise in the number of first time private plane buyers brought into the market by today's bargain prices for private jets.
Though the early Lockheed Jetstar had four, most production business jets have two jet engines, mostly rear-mounted podded engine. If mounted below their low wing, it wouldn't allow sufficient engine clearance without a too long landing gear. The HondaJet is the exception with its over the wing engine pods. Dassault Falcon still builds three-engine models derived from the Falcon 50, and the very light jet market has seen several single-engine design concepts and the introduction of the Cirrus Vision SF50 in 2016.