I live in Texas and yesterday was 108*. I just bought a 110V, 13k BTU portable AC/heater/dehumidifier combo unit for around $500 for my 400 sq. ft. shop/garage. I looked at the split minis but I could have, literally, built a new shop for what those things cost (around $4K installed). I have only had it for about a week, but it seems to make a huge difference. The key is insulation. I also added extra insulation to the attic over the garage as well as putting weather stripping around the garage doors. All of this will pretty much seal off your shop, so you will need some kind of air filtration to keep the dangerous sawdust down as well as circulating the air. As I said it was 108* yesterday and the shop was a "comfortable?" 85 to 90*.
Edited: I should have said that the shop was 85 to 90 without the AC unit being turned on due to the insulation and weather stripping. That is a significant amount compared to outside temp.
Fort Worth, Texas
City where the west begins.
Last edited by curiousgeorge; 08-10-2012 at 12:56 PM.