How much does a Flexjet cost?

I'm curious to know, what is the approximate cost of owning or leasing a Flexjet? As someone interested in private aviation, I'm trying to weigh the financial implications of such a purchase or rental. Could you provide me with a general range or an average cost that I can expect to encounter when considering a Flexjet? It would be greatly appreciated if you could also elaborate on any factors that might influence the final cost, such as the model, maintenance, and operational expenses.