I smile at these "HOW MUCH!" threads. Fifty to one hundred quid to use the facilities and be looked after and only once in a blue moon. C'mon
At the aerodrome I once ran we got fed up of trying to extract £10 from singles and £20 quid from twins so we left a box at self briefing for 'Donations' and guess what? Yup, we made more money and no hassle.
The only bad apples were pilots who knew about our reciprocal arrangement so always seemed to arrive from there.
An AC11 - what's that like? Permit type?
SGC