I would like to add to this building project, that you are considering. I too am looking at putting up a building on my property and have read these last post with great interest. One thing you may look into and I did this with an older building I owned in Montana. For insulation look into the spray on insulation. This stuff works great. Takes little heat to warm in the winter and little air to cool in the summer. Although in Montana I never worried about trying to keep it cool. Just my 3 cents worth.