Are you required to GFCI all the outlet circuits?Yep! I have one of those installed in the first outlet of every circuit. Surprisingly, the air conditioners came with GFCI heads already installed on the plugs. But, yeah, it's required by code.
I'm assuming all the outlets are on 20 amp circuits. Did you put in any 30 amp 24 and 60 amp 240 circuits to accommodate future heavier equipment (air compressor, welder, etc.)All the outlets are on 20 amp circuits, and the outlets themselves are 20 amp. The AC units required a 20 amp 240v circuit and I have two of them installed. Each AC unit on it's own circuit.
You're not the first person to ask about a welder, and that amazes me for several reasons. First, I don't weld. Never have, never learned. And, with the eye problems I've been diagnosed with, welding isn't in my future. However, two of my three sons weld, and they have these amazing little MIG/TIG welders (one's a Miller, one's a Lincoln) that they run on standard 110v, 20 amp circuits. But no, I'm not a welder and ever will be. My air compressor is a little Harbor Freight unit that runs on standard household current.
You have air conditioners, any provision for a large wall fan? On low it can exhaust gunsmoke, on high move enough air for cooling.We talked about exhaust fans today, during our lunch break. Some sort of exhaust fan is in the works, but I haven't figured out the details. I have plenty of breaker capacity in the panel in case I want to install circuits later, but right now I think I'm good.