Awesome bro. You're gonna be so stoked on the co2 man!
If you need any advice or help with the co2 give me a holler and I will share all that I know. I have 100s of hours research and experience on the subject.
Yeah, its a spendy investment. The crazy part is adding ac, dehum, is about the same as adding 2000 watts. When I initially got AC and a dehum, It nearly doubled my power bill, ouch.
Sounds to me like your gonna want to run a propane burner or 2 with the size of your new space, if you have natural gas you could do that instead which would be P-I-IMPin'. You'd be at the welding shop every week if you ran tanked co2. Anywho, I am excited for you and can't wait to see the new space. I will be using nat gas in my commercial once I am at that point.