I think you can safely add the passenger compensation scheme for EU operators to the airline expenditure.
Additionally, the so called cost savings of not having any, or inadequate, engineering cover down the route can prove to be false economy. I don't think you would need many AOGs down route for the engineers to effectively pay for themselves. Worth their weight in gold every time.
Trying and probably failing to save on the pennies, but having to pay pounds instead. Decisions Decisions.
