Fans of Chuunibyou Demo Koi ga Shitai are wondering why, when Rikka returned to her childhood home, there was nothing there but a vacant lot. Wouldn’t it be more natural to find the house there, but with a strange family living in it?
This probably reflects the fact that single-family homes in Japan tend to have very little resale value. Would-be homeowners strongly prefer to buy a new house from a developer or to buy an empty lot and have a house built to their specifications.
So the family probably sold the house to a developer who tore it down to make room for a new home.
This may date back to the very ancient Shinto tradition of tearing down buildings every 20 years or so (or earlier if the owner died) in order to get rid of accumulated impurities. Or maybe it just reflects the Japanese preference to pay extra in order to get the best quality. Buying a used house implies choosing something that’s not exactly what you want in order to save money.