My dad just built another garage at his house, a lot bigger than a 2 car and it's got a kitchen, bathroom, viewing area, workshop, and loft. Our concrete prices must be down in this part of the country because, his slab entire slab, side pad, and driveway was $10K.
bathroom
unfinished but, pretty much finished. The floor has been stained now, couches, and a rug added.
ceiling, which is actually wood flooring.
Kitchen and side door.
