The cost of building materials are still high so ...

Oh hell No.... where are You Located? I'll build it, and it WILL be done Correctly and up to Code. Code here is probably more intense.... hurricanes, uplift, ect.... do you have a set of prints? I can give you a take off on the materials?
no prints ive had several guys come and look and say they will give me a quote but never do Here is what want my garage is 16 x 30 i do body and paint in the same bay thats not good i want to ad on to the back to make it a paint booth. its going to have a garage door in between the two bays so when im done with the body work i can push it into the booth no other doors , windows no wiring insulation nothing im going to do all the inside finish work the ground need to be leveled alittle for the floor i can do all that and frame it out i just need the floor poured and the building put up