we're both in the same spot it sounds. I just closed on my house about 6 weeks ago. I am planning on building a 36x28 shop, in phased construction. Just for the structure(6x6 and 4x4 posts, roof trusses made from 2x6's, all treated lumber) and metal roof materials, I'm at about $2600+tax. We'll call that phase 1. This does not include any wiring or plumbing, just basic buildng materials. Mine is gonna be 3 bays, but with only 2 walled in, the third will be an open wing to park the daily driver under. To pour the slab for the 2 enclosed bays, I'm looking at about $1k, figuring approx $100/yd for the concrete. I'll call the slab phase 2. I haven't calculated the cost to frame/wall the 2 bays yet, as that will be down the road a bit. Phase 3 will be walling up the slabbed 2 bay area, hanging gargae doors, and doing the electrical. I'm guessing I'll end up with 7-8K in it. I live in Ga. and materials might be alot different where you live.