I know all of you say that paintball co2
won't last long enough for the initial cost reductions but how about this:
Paintball ASA 8 dollars new
1200 psi gauge 3 dollars
Needlevalve It's a clippard I got for ~18 but you can find MUCH cheaper needle valves.
Vinyl hose - 2.50
Paintball tank 24oz ~20-30 filled used or 30-40 new filled.
You could have a 1.5lb tank for ~60 dollars ready to go.
And here is a setup on an old 12oz that I'm using for testing all the fittings. The 12oz isn't what I'm going to use...its hydrotest expired several months ago.