I was thinking about doing this but I just bought a super quiet air compressor. You could just level the dirt and use pea gravel or pavers so you don't have to pour concrete.
Shed:
https://www.amazon.com/Patiowell-Outdoor-Storage-Lockable-Backyard/dp/B0BP952Q7N/?tag=fabo03-20
Sound Deadening panels:
https://www.amazon.com/LEIYER-Upgra...e-Quick-Recovery/dp/B0C5J49RL6/?tag=fabo03-20