[qengho]

It is incompatible. Just because a property is vacant doesn't mean it is "undesired" or "inefficiently-used".

As long as governments continue to rob their citizens via taxes, people will do their best to not be robbed, resulting in "black money" (which is actually "white money" since none of it went to fund wars and murderous statist schemes, as opposed to the "red money" which is tax paid and so did help fund wars and statist aggression against peaceful citizens).

This "white money" will then find a place to be invested where it receives some ROI, unlike the banks and bonds and stocks that have been completely destroyed by government meddling in the economy. That is real estate or precious metals and that's where the "white money" will go.

The entire "problem" (if it is one at all) is created by statist violation of property rights through taxation, in the first place. Further statist property rights violations will only distort things even further. Let's say you introduce squatting "rights". Well now you know what happens? Nobody's buying real estate in your country any more. All the "white money" flows to alternate investments and real estate in other countries that don't have squatting "rights".

It's basic human action. People don't want to be enslaved and robbed from. And they will do everything in their power to avoid it.