Why the investment funds have to build the houses? Houses has been built/funded from zero by the future owners since forever, either individually or through cooperatives. That way, "investors" don't need a positive ROI, and they happily lose money overall if they get a home.

I know some people that are currently "willing to invest" in buying a ship container or two and transform it into a house to get costs down. The problem? Regulations don't allow them to put the container in their own property.

Using a shipping container is almost always a stupid plan compared to just putting up some wood. As much as I want to make zoning more flexible, I'm not in a rush to change that particular regulation.