That will likely be your largest variable cost. Also, what type of utilities are you going to run to the building? Are you installing them yourself, or do you want this to be included in the cost of the building? All those things affect the cost.

I built a 36 X 40 metal building about 7 years ago. I paid $24,000 for it, or about $17/SF. The floor is unfinished, and I didn't pay to have utilities run to it. After it was done, I ran the electric to it myself and did all the interior electrical work.

I priced out Morton and other company's package buildings, and they were significantly higher. What I ended up doing is finding a building contractor that I trusted and had him put up the building on his own without buying a steel building package from Morton/etc.