[cjtrowbridge]

The answer is nonprofit Community Development Corporations. They get lots of special funding sources which allow them to buy or develop housing and rent it out affordably.

I recently finished a degree focused on this model at SFSU. There are a few really good examples like CCDC and TNDC in SF. Both of these have acquired about 4,500 units of housing so far, all of which are affordable. Many of the other districts have or want something similar.

This is the only general-purpose solution I've found to nonprofit affordable community development of not just housing but also many other types of infrastructure projects.

It's just not possible to build for-profit inventory that's affordable; the cost per unit is too high. But there are lots of exciting ways to fund nonprofit affordable housing, and the CDC model