Have you ever considered a steel framed building and save a few grand? That's what I did, so that I could use that savings to put a bathroom in mine. My building is steel framed but it has 20 year warranty's on rust and a 60 lb psf snow load. the Mexicans who put it up were running on that roof while building it. I took photos. I had an insulation supplier locally arrange the foam spray job. I used barns dot com for mine.