Why not take a look at the way Habit for Humanity manages the building of their houses. Every single homeowner, no exceptions, has to help build their own home. A requirement for renters could carry the same stipulation. Homeless people have lost all pride and have no reason for hope. By assisting in the building of their dwellings, they would potentially recover hope and pride. 

A point to consider is that whenever a person has a vested interest in a project like this, they historically take much better care of their property and the surrounding neighborhood.