It depends, upon your definition of house and on what kind of technology you have access to to build your house with, whether it takes months or years or days o

It depends, upon your definition of house and on what kind of technology you have access to to build your house with, whether it takes months or years or days or even more or even less than that. See this news [1] regarding the time issue. So that's not the main big problem, the main problem is the cost of land. Today that has become a very big problem and the concentration of jobs in certain cities (parts) only has exacerbated the problem. The rich people have already purchased huge swathes of lands in important cities/areas and this has created/added to the problem of inequality in a very important manner. This problem can be solved by taking away the excess land from the rich after allowing them to keep some minimum amount. Another factor is population and its vast growth. The population and its growth should also be checked/controlled in a very big way. [1] http://www.huffingtonpost.com/entry/3d-printed-houses_n_5773408.html http://www.huffingtonpost.com/entry/3d-printed-houses_n_5773...