What's better than rent controls? A tax on vacant lots and unoccupied housing. While rent controls make it less attractive to supply housing, a vacancy tax makes it less attractive NOT to supply housing! A vacancy tax of ₵x per week makes it ₵x/week more expensive NOT to get a tenant, and thereby REDUCES, by ₵x/week, the minimum rent that will persuade the owner to accept a tenant.

If NEW buildings are exempted from rent control in an effort to encourage construction, the stock of rent-controlled housing becomes an ever-shrinking fraction of the total housing supply — unless the exemption is only for a limited time, in which case there is less incentive to build! A vacancy tax avoids such conflicts; it unequivocally tends to increase the effective supply of housing and therefore to reduce rents.

Similarly, a vacancy tax on commercial property would reduce rents for job-creating enterprises.

With a sufficiently heavy vacancy tax, evictions due to foreclosures would be consigned to the past, because the foreclosing bankers, in order to avoid the tax, would want to retain the current tenants or former owner-occupants as continuing tenants. Of course the existing stock of empty foreclosed homes would be immediately made available for rent, as it should have been all along — not just drip-fed to buyers over a period of years.

And the political trump card... Avoidance of the vacancy tax would initiate economic activity, which would expand the bases of other taxes, allowing their rates to be reduced, so that the rest of the city/state/country gets a tax cut!
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