.. so I'd like to get off cheap. Really cheap.

I found a place to get a refurbished Porter Cable finish nailer. That
leaves the compressor. I've been looking at this tiny 1 gallon
Campbel-Hausfeld model, 100psi max.

I have a 2 gal single tank Craftsman Max 125 psi. It also comes in many
other tradenames..made in China.
They go on sale for $ 99.00 I now see 3-4gal compressors on sale at Pep
Boys for under $ 100.00

That said, the finish nailer I bought says MAX 100 psi. I put up 1000 lin
ft MDF baseboard and about the same in 1X4, 1X5 VGFir with it 2 yrs ago,
compressor set @ 100 psi and it worked great. Cheap gear-worked well

R