It's a lot easier to do something beforehand. It bears repeating that, although federal tax authorities collect various types of taxes, they don't collect property tax. To do so, they would need to set up a new system, a new mechanism, one that will probably be here to stay once implemented. That is why it's better to think ahead.
Just as the federal government has no authority to regulate housing, it has total authority to levy whatever taxes it likes. This is a situation where the federal government has levied a tax in an area it has never chosen previously. There will be a price tag to setting up a system to administer and collect property tax, and it will all be for naught if the tax is ultimately deemed, not a true tax, but a hidden tax whose real intent is to interfere in housing matters.