Ok Doug here's what you need to know. My Mate Tony only uses Tamyia Acrylic and uses 10% Tamyia Thinners. Some modellers use the Vallejo paint range ( they have a formula which is supposed to be for airbrushing ) but Tony doesn't rate it at all. All other Acrylic's tend to have poor coverage , run's , blotching and almost always end up blocking the airbrush with dried up paint in the nozzle.
For covering large area's i'd suggest using a matt car spray over an undercoated base of black for most darker colours or white for the lighter colours. Halfords 500ml Tins are pretty good. If you do make a horlics of things and you need to remove Acrylic paint ( if the painted bits are plastic card or metal that is and can be removed and placed into a tub , ice-cream tubs are ideal
) then soak them for 24-48 hours in cheap brake fluid , remove and gently scrub under warm water using a tooth brush but remember to wear gloves and have the room well ventelated too as the fumes wouldn't be great for your health. For purely metal parts that the paint hasn't taken to properly use the above or use Mr Muscle oven cleaner spray which works especially well on Enamel paint's on any surface.
If you want to re-use the brake fluid buy a cheap metal sieve and line it with 4 sheets of kitchen paper. Use this to filter the brake fluid into another container for reuse. It will be discoloured but will work up to 4 times before it should be discarded properly at the local council dump. Just make sure that no water gets into the brake fluid and it will be ok.
Hope this helps.
Davie