My intention is to make rent seeking less attractive as an investment. Once residential units are bought it tends to become permanent, over time a higher and higher % of space is for rent. The other choice is to mandate equity via rent. Of some one buys a house and pays 10% down. Then rents it, the tenant pays the rent which pays the mortgage, but the tenant gets no equity. Grant equity as a % of mortgage paid during his tenure - if he moves the land lord owes him money. This will make people buy out right = more taxes etc.