In the past, people were able to buy a small piece of land and develop it themselves. Literally build the house themselves. Over a long period time if necessary to spread out the cost. They also built 2-4 family homes so they could bring in some rent or house a family member.

None of this is really allowed anymore and it's very hard to find a piece of land to do it with. Enabling this sort of construction and forcing or incentiving small plots of land might open up options for people on the lower end.