Housing Bubble 2: Return of the Ugly

Nah, too low, doesn't snowball quick enough, and being rich doesn't entitle you to extra housing when we have a shortage. Double the property tax every time, at the federal level. The prime home has normal tax to the county. The second and beyond homes have extra taxes owed to the IRS. You can also sell to the government for half price at any point you declare yourself unable to find a buyer for an extra home.

This gives the government land to construct denser housing and sell it at cost.