We start with so many restrictions on new housing like height limits, parking minimums, restrictions on rental units, trouble getting a building permit that there is no free market on housing. If we had a freer market on housing in developers would buy up older buildings, knock them down and build taller apartments or condos. And they would be built in the areas where people can get to good jobs and walkable neighborhoods because that's where property values are highest and the developers would make the most profit. A freer market would put housing where it is most needed. I say freer because perfectly free is probably impossible. Housing access to the best job markets would lower unemployment and stimulate the economy and access to more walkable neighborhoods would reduce obesity, diabetes lowering healthcare costs. People with more money would probably take this new housing but then that would free up older housing a little farther away for people with less income. Lowering the market price of housing would also lower the amount of subsidies needed by the lowest income people to get housing.