I guess $15,000 at the bottom of the market would not tend to have huge localized effects on housing (I think people would be more inclined to move towards cheaper housing than to compete for scarce housing; the $15,000 eases pressure on moving to better paying jobs).

For goods like food, the supply is pretty freaking elastic.

The bottom of the market is exactly where those depending on basic income reside.

A "move towards cheaper housing" by others would be competing against basic income dependents within this market segment.

This is what I meant by within some defined boundary. Here, its the lower end housing market.

Right, but it wouldn't happen in a geographically constrained area and location is the factor that really drives crazy housing prices.