Note permit, not tax. But essentially the same thing.
One big cause of inequality is from property ownership versus renting. Especially where people or businesses own multiple properties. They gain from increased property prices that they do not earn, and get richer still (relative to poor people). While I could prove it with statistics, it is self-evident – wherever rich people invest is where they get the most returns, and the greater relative advantage.
While a lack of affordable housing is common throughout the world, it is especially bad lately (in the AirBnb era) in touristed areas. So we can start there. Any house owner who does not reside there, must pay for a permit for that luxury.
We start off by telling house-owners in the area that such a permit, that has an annual cost, will be coming soon. And the intention is to eventually make it costly enough that some of them will sell. Presumably a resident home owner will buy it, seeing as they don’t have to pay for an ongoing permit.
Every year the local council/authority will increase the permit cost until home ownership starts increasing.
The permit proceeds go to the local council/authority, and can only be used for creating social or public housing. The permit fee will be based on assessed value, the same as property rates and taxes.
The methodology will be similar to self-reported income tax, in that the government will have ways of checking on people.
Obviously any property owned by a company will require the company to disclose the details of who owns the company if they wish to try and avoid paying the permit. Checks could also be combined with the state and federal tax systems – wherever the beneficial owner of a property claims tax deductions, and ownership records can be checked for the same name owning more that one place. International travel records could check to see if they are ordinarily resident. And so on – many ways of making sure people are compliant.
This is not the only solution – just a different and perhaps a new one.
People who are leveraged will suffer the most/quickest because such a permit could mean they start losing money. But even rich people who own many properties freehold will be affected, and they might consider that selling their properties and investing in something else would be more appealing.