Feng Bing， Head of Business Jet Department， Ameco：

Long-range business jets can be modified to meet the needs and preference of its owners. But as everything is completed under strict restrictions of airworthiness regulators， aircraft modification could be much pricier than that of car or yacht. Function is always the first priority in modification， followed by weight and cost. Every small change requires airworthiness certification， including the inflammability， strength， length or width of a material， before and after modification. The more you modify， the more materials you use， the heavier the aircraft， the higher the risk， and the harder it will be to obtain airworthiness certificate. The completion cost of a business jet ranges from 1 million USD for a Piaggio P180 to over 50 million for a B747. The interior modification of an ACJ or BBJ VIP jet might take 150 staff a year and a half at a cost of 10 to 30 million USD. The first 747-8VIP business jet Boeing delivered to Qatar in 2012 took 2 years and 120 to 150 million USD for interior modification. That said， if you have all the time and money， you can even transform your jet into an Air Force One.