I was trying to get an idea of what Japanese house prices are, but I couldn't find much beyond the cost of a new house. Which is less than in the US, but not by much more than 10-20%. I understand houses in Japan don't typically appreciate in value like they do in the US though. They like to buy new and don't see it as an investment.

I assume a huge factor has to simply be that Japan's GDP and population growth has been basically flat for ~25 years.