My current shop is not air conditioned, and if it were it would cost a zillion dollars a month in electricity. It is a metal building with NO INSULATION whatsoever. I do have overhead doors at the North and South ends of the building. In this part of the world we have a prevailing SouthWest wind, so this helps alot with both doors open in the summer.
I DO, however, have a walking beam overhead. There is no electric hoist on it, just a chain fall. I built this from pipe hanging from the rafters with some "dollies" from an industrial material handling "carrousel."
My shop looks like H$!! because there is too much junk crammed into it, but functionally it's not bad. Now if I could only come up with a lift and maybe a few hundred additional square feet.
Have a great day,