Isn't that the wrong question? Presumably unrestrained builders would be happy to sell to anyone, so you need the build rate where it is not profitable to inves

Isn't that the wrong question? Presumably unrestrained builders would be happy to sell to anyone, so you need the build rate where it is not profitable to invest in properties, not the build rate where it is impossible for investment to buy all properties. And then it's logical that the one is lower than the other.