RE:RE:New factorFrom OEM side, pre 2008 they used to take small deposit from buyer at time of signing. And as the aircraft got build the buyer would put more down to match the increase value of the aircraft. By the time the aircraft is completed the buyer has paid for most of the airplane. This protects the manufacturer. Recently I was told that now most of the OEM require 60 to 70% upfront at signing. This is protecting them from holding on to partially build jets just in case the buyer backs out or files for bankruptcy etc.
I was also told that OEM's have taken a very conservative approach to increase build capacity so that they dont get burn like they did in 2008/9.
As how the buyer pays or finance these all depends on the client. Fractional ownership get financing like a business just like any other large capital investment. And the lender is very cautious of the resale value of the aircraft. So for now Bombardier jets used price are up ~20% and Gulfstream is down ~6%. Lenders will fill more comfortable financing Bombardier jets because of resale value.
For large jets like Global 7500, if they are bought by individuals then they are usually not financed. Those wh can afford $75 million jet pay out of their pocket. They dont finance.
What I have said above is base on what I have read in aviation related articles and from industry networking and trade shows. Take it for what its worth.