Has anyone had experience with just a concrete floor? My husband used to do concrete for a giant PreCast company and he just bought a portable concrete mixer which is rapidly becoming a new toy. . .
Concrete is fine for a enclosed building but in a partly open building you will run into drainage issues. Unless you put in drains. That could work.
A concrete mixer is a great toy!
You may have to reign him in, lest he attempt to pave the earth:
https://www.reddit.com/r/pavetheearth/
“We believe in a completely Paved Earth. Earth is cursed with trees, shrubs, grass, and scurrying creatures. With every breath we act to right this terrible wrong.”