ello fella well you got a great bunch here to help. I can give a bit of advice but not huge amounts. I
airbrush as well as doing models so this is what I find helps
get a comp that has a tank or a system that gives pulse free air this is really a must or you will never get a smooth stream of air,
make sure you have somthing to clean the air and a moisture trap, small comps are the worst I have found they get hot and it gets worse.
I found a little Iwata unit on ebay and bought that for around £140 a smart jet turns on and off as you use it. Mine only goes up to 30psi I will get a better one that goes to 60 soon though better all round for me as its not just models I do. Im not sure if you can get them from the shop here but if you can I think you will get the best advice there is here.