You'll want a good sized compressor with good constant CFM so it will keep up.
Sandblasting knocks the hell out of your compressor, and theirs nothing worse than running out of air midway through a project and having to wait for the compressor to catch up. Also a good quality water separator to keep the moisture out of the line.
As far as the blaster itself, I like the pressure pot blaster. It seems easier on the compressor and takes less air than the gun+tube type.
Just my personal opinion.
Vic