And with that every single house around also increases in price, because house prices are often dictated by what comparable houses recently sold for. As if they weren't already expensive enough. Besides, I don't think lack of profit prospects is currently a bottleneck for house building. There seems to be tons of regulations and control to what is allowable to be built. And from, there it doesn't matter that building a house would be 20% profit, if it's illegal to do so.