[failuser]

You’ll need a construction cooperative. IDK if those can compete with large construction companies due to the economy of scale. The construction cooperatives were a staple of late Soviet and post-Soviet Russia, but were essentially outlawed later to make way for large construction business and mortgages-backed construction.

[bluGill]

I'm not against them, but they are not the right answer for everyone. They are great if you want to live in the same apartment for a few decades, but if you move they become tricky.