pole shed questions

I built a 40X72X14. I wish I had gone 48x72x14. It accommodated pretty much any lift I wanted. I have a 36" walk in door, 2- 12x10 roll up doors and 4 windows. I put my work area on the south facing end. I have a 4' space between the roll up doors that I have hung 2 blues tarps on high tensile wire to separate the shop into a work area and storage area. The tarps also hold heat in my work bay so I don't heat the entire shop, just where I'm working. I agree with the others, pour concrete before you start putting anything in the building. I would contact smaller contractors to do a turnkey job. My contractor started on a Monday and pulled off the job the following Thursday. There were 2-3 people working on it.