I forget where (I want to say St. Louis?), but there was a neighborhood where they experimented with brutalist housing. Basically, each home was a single concrete pour. Just set up the mold, toss in some steel bars, and start dumping concrete.

Each one was dirt cheap. IIRC it was like $300 in materials for each house at around 1,200 sq. ft. in the 1970s. It didn't take much to add electricity and plumbing, either. The houses are still standing today without anyone working to preserve them, even as other homes in the neighborhood have been abandoned or condemned.

So why wasn't this done anywhere else? Realtors didn't like the low commission rate, so nobody wanted to invest making these homes anywhere else. The half dozen or so that were made came out of the architect's own pocket as a proof of concept.

Edit:

Gary, Indiana is where I was thinking:

Gary Indiana Concrete Historic District

They used a method developed by Thomas Edison to make cheap houses.