The problem lies with the market

what we felt as we faced the vacant houses problem.
In order to solve the vacant houses problem, we have to start from the root of the problem, that is, occurrence of vacant houses.
There are various reasons for vacant houses, but basically if the owner can sell the vacant house, there will be no problem.

The problem with "property tax" is that they leave unused houses built because they don't sell.

Even in the case of "succession" if it can be sold, someone will live there and it will not be an empty house, and it will be used effectively even if no one lives there.

If the market value of the house rises and the house sells, the "real estate as demerit goods" will no longer be a real estate as demerit goods.

If you can sell the house before it becomes ruined due to lack of proper management, there will be no "ruin".

The price of goods changes according to demand.

If more people want to live in used houses, the price of used houses will rise and the market value will rise.
If the number of people who want to live in new houses decreases, the price of new houses will decrease and the market value will decrease.
In other words, to increase the value of used houses, it would be better if more people wanted to live in them.

vacant house problem in Japan

The vacant house problem in Japan is still at the stage where it can be solved.
This is because even though we have 8.46 million vacant houses, we are still building 950,000 new houses in a year.
(国土交通省 総合政策局「建築着工統計調査報告(平成30年度計)」による。)

This is fortunate.
For example, while the number of vacant houses has increased to 8.64 million, if the number of newly built houses is 0 in a year, the number of vacant houses continues to increase even if all the demand generated is for used houses, and the only way to reduce the rate of vacant houses is to demolish them.
If that happens, the solution will be extremely difficult.

But Japan is different now. There is a demand for 950,000 new houses. Even though there are vacant houses to live in, they are building new houses.

If we could allocate this to the demand for used homes, In other words, if many "people who are going to live in a new house" become "people trying to live in a used house" the increase in the rate of vacant houses can be stopped.
In order to do so, it is necessary to eliminate the tendency to build new houses.