The "problem" is that we let people claim the "rent" is X for certain people and "Y" for other people--both at the same time. Just stop that.

The "solution" is that you should have to pay tax on what you claim the rent is after a small grace period (Less than 24 months certainly. Probably less than 12 or at least prorated starting before that.).

If your financial agreement requires and claims that the rent is $5000, no problem! Then the tax authority should expect to receive the tax revenue they would expect if someone was actually paying $5,000 in rent to you. If you want to leave the space vacant even after paying the tax on the revenue--have a blast.

That would short circuit all the financialization shenanigans.

If the property is devalued, the property taxes lower accordingly. Portland, Oregon has been facing this problem recently. The devaluations caused the tax revenues for the city to drop, which in turn has caused budget issues.

For example, "Big Pink" is an office tower in downtown Portland. It's last sale was for about $370 million. Out of desperation in a saturated market, the owners sold it last year for about $45 million. No one - the owners, the city, or the citizens - wants to have the vicious downturn of values, and there is no easy solution. Adding a vacancy tax just exacerbates the problem.

Georgism FTW