That is a nice sized workshop. Dont forget when you pour the slab to leave a cutout so you can dig a tunnel to access the basement. You could stockpile all winter long in the front room of the shop and never get cramped for space.
My wife mentioned yesterday that she wants me to build a really nice detailed doll house for the triplets to play with in a few years. Looks like the builds and conversions may be pushed back again. I think I might have to build it to 1:14 scale.
