johnrov,
I have a VL and I'll try to answer as best I can.
- I would think that a regular color-cup full of paint would cover an average 1/48 plane (modern jet) at least once and possibly even twice depending on how thick you apply it. However, I'm a bit stingy with paint, preferring to apply it quite thin, so perhaps others will have different advice. If you hold the trigger wide open, it'll consume the entire paint cup in about 15-20seconds depending on the psi your using (I'm guessing here.)
- I'm not the most experienced with washes, but I usually use a heavily darkened version of the base color as a wash. I don't like black because it seems to drastic. A darker grey works pretty good too.
Hopefully other readers will have better advice.
M.