[mickmate]

The thickness you want to weld will dictate the machine specs. Good rule of thumb is 1 amp per thousandth of metal, in other words the 1/4" will need about 250 amps. That is getting a little high for an aircooled torch but will work fine for occasional or discontinuous welding. A cooler adds more on the maintenance and quite a bit on the expense. Check machinery auctions I have seen some real deals on used machines from trade schools etc. I would also recommend a well known brand for parts servicability etc. Miller, Airco, Lincoln etc. You'll have a blast with one they are very versatile.