That's good, because if they can't pay, their house is up for remodelling too. /sarcasm
Also, you need to figure out how you define vacant, and how to track it.
If I relocated for work, and use the house 3 months a year and every other month for a weekend, is it vacant? How do you tell?
The definition of vacant is something that would have to be figured out, but it's not impossible. For example, you could do a generous 6-12 months of the year occupation without taxation, and then a sliding scale from there. (So you pay 0% of the new tax at 12 months yearly occupation, 0% at 6 months, 50% at 3 months, and 100% at 0 months.)
Imagine you worked all your life and now you just want to enjoy your peace in your home for your last years. You really would not want to move and I am very against driving old people out of their homes, even though I am one of those young people with a small apartment also seeing empty and unused space everywhere.
Not everyone can do that easily. I would not know how that works and where are the downsides. I can learn it, sure, but for an 80 year old this would be real stress, having to figure unknown contracts out - and not getting cheated. Old people are a prime target for frauds for a reason.
This is why complaining about rising property taxes is almost never about the elderly people who actually live in the house. It's about their children that want to inherit the house without paying off their parents' property taxes.
People in different countries experience different realities.
> The reality is that the same thing, in effect, happens if you stop paying property taxes. The tax builds up, etc.
and in many places worse things will happen to you if you stop paying property taxes.
I think Japan is one of the outliers where pretty much all property value is locked with the land itself, as buildings depreciate not appreciate.
That was my point, not binding the value just to the building itself.