The largest VIP jet will, perhaps, be a retired airline Airbus A380 purchased for conversion in 2018. I know who sold it, but not who bought it—they’re not telling. It’s not certain the aircraft will make it through the process because the engineering is so daunting and frightfully expensive. The one VVIP A380 splattered all over the ‘net as the world’s most expensive private jet doesn’t actually exist because Airbus canceled the project for that very reason.
Otherwise, the largest VIP jets are 747s. They’re owned mostly by governments and sultanates, including 747’s 92–9000 and 82–8000, eg the jets usually known as Air Force One. There are around 30 of these monster ships.
A retired Japanese “Air Force One”’ (replaced last August with a 777-300ER), a 1991 747–400 now called N7474C, is under contract for purchase. It sold for about $25MM, and is undergoing pre-buy as I type.
Sands casino owns a couple 747SPs. Last year Kanye and Kim released a video flying on one of them.
Turkey put a new head of state 747 into operation in 2015. It’s an 8i, the largest 747 variant. It’s pretty spectacular:
