The #1 problem for no low cost housing is an artificial shortage of places to put them.  Why do we need so much space for a house,  why are the ravines with >15% grades so dangerous to build on?  In town there are old houses still standing that would not be allowed today.

No Rentals is different I have had 3, 2 of  them are gone now because I was treated badly by 2 single mothers with children that we tried to help with low rents and working with them for payments.  They left the houses trashed and absolutely filthy, and also left owing months of back rent.   At the least without spending 1 penny they could have cleaned the house, picked the junk up out of the yard, and not thrown food on the walls and ceilings.