I think I can keep the clinical and marketing costs below £15000 if most of the monitors, trolleys, ventilators e.t.c. are rented rather than purchased.
The aviation costs I'm not quite so sure about, one of the reasons I'm posting here is to try and find out more about it.
I forget the helicopter used by London HEMS but it uses a jetstream rather than a tail rotor for stabilization and the main rotors are higher so it can be used in urban areas without decapitating people who don't have the sense to stand back.