I'd vote for a system where the government was obliged to purchase property at a 25% discount to what they assessed it at, if the owner chooses to sell it.
In theory, this idea is really good, but I think it needs a certain amount of refinement.
The largest, obvious problem is that transaction costs are enormous.
That might be mitigated by adding a multiplier to the forced sale value: say 1.3 or 1.5. I have no idea what an appropriate value is, but it seems like the sort of thing that could be determined empirically.
On the commercial side, there's all sorts of complications (e.g. tenant improvements) that I just don't know enough about to even talk about intelligently.
It might not even cost the county tax assessors much, some of these abuses are so blatant that even a private citizen could buy out the building under that policy:
https://dailycaller.com/2018/08/14/apple-hq-200-dollars-sant...
> Apple, history’s first trillion-dollar company, is arguing that a cluster of new buildings at its headquarters is worth only $200 in order to lower its tax burden.
> The trillion-dollar tech giant claimed in an appeal the value of the “cluster of properties” is worth $200, not the $1 billion value given by the Santa Clara County’s tax assessor — elected officials who determine property value for tax purposes.
I'd call it "disruptive innovation" to buy out Apple's headquarters buildings for the $200 it thinks they're worth, rent them back to Apple at the maximum price the market will bear, and pay Santa Clara County it's fair share in taxes.
To be fair, another source says it’s unclear if that is $200 or $200M which is a big difference.
Apple does pay $56M in property taxes per year in Santa Clara county and is the largest property tax payer in a county that includes Google. If property taxes there are 1%, that would mean $5.6B in assessed value.
Specifically, this would link a town's ability to raise taxes dependent on its existing financial situation: A poor town that would run into difficulty obtaining financing for multi-million $ purchases could easily be scared into undervaluing properties, further weakening its financial position.
While they could (in theory) flip the property and earn money, the market for large retail properties would seem to be at the rather illiquid end of the spectrum. And even with good prospects of selling, I wouldn't want to be the small-town mayor (who are, I believe, usually unpaid) suddenly shouldered with the responsibility for such a transaction.