I recommend you to choose a company that has been in the market for a long time. It is also important that she had new aircraft. Our friends recently used the services of a charter company and flew on the Falcon 7X. They were delighted. 7X is a pretty good airplane and they use a special certificate (card). I found information on Wikipedia about 7X on the Wiki - it takes 12-16 passengers. (link to Wikipedia https://en.wikipedia.org/wiki/Dassault_Falcon_7X)
I found a picture describing the aircraft.

Source - jet588.com/dassault-falcon-7x
They flew to Las Vegas, they got a modification with a maximum number of passengers of 14 people. So specify in advance how many passengers the plane can take on board.