The above is very accurate. Quite often, the number that gets lost in the shuffle is the resale of the aircraft. If you are trying to operate an airplane ona 135 cert and getting good utilization, care for the aircraft goes down the tubes. The paint and interior wear out much quicker, the crews care less for the little things and the pax treat it like, well like a "rental". When you talk about another $300K at selling time, how does that impact the total cost of ownership? If your owner is financing the airplane on a 20 year amortization, he may be writing a big check at sell time. You need to make sure you have a finance type in your fold (not the aircraft broker or charter management firms people) that can evaluate the project start to finish, and they need to understand the used a\c market. I will say personally I think that the charter model of cost mitigation is more fiction than reality, since on total cost the owner usage needs to be so low that they may as well charter and skip ownership.