The most economical option is chartering, which doesn't require any cash upfront (other than a deposit) through companies like Tradewind, Sentient, and Solairus, (which we took home from North Carolina). Of course, there are the old standbys like NetJets and Marquis, who sell fractional ownership (like 1/16th) of a single jet for upwards of $100K. One step down from that, pricewise, is the jet card, where you buy a set amount of hours from a company like Nicholas or Private Jet Services, and can use those hours for different planes. Then there are membership models like WheelsUp, where you pay $17,500 as an initiation fee to fly in their fleet, and then a $8,500 annual dues fee starting the second year. It's like a country club—only you're guaranteed access to a KingAir350i or Citation Excel / XLS instead of a golf course.
While today’s connected society allows people to access a vast wealth of information, right at their fingertips, the reality of the Web is that it provides a very incomplete picture of private jets for sale or the private jet marketplace. Indeed, many of the best aircraft for sale never appear on the Internet, as they’re bought and sold among Aircraft Brokers for their clients without ever being listed for sale.
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.