I just heard about the rental price ratio for that apartment, and it was significant back when gap investing was possible, allowing people to buy multiple houses, sometimes as many as ten, without any capital by combining loans and rentals. Is the current decrease in the rental price ratio because rental prices are dropping? Or is it because house prices are rising too quickly while rentals are disappearing? If the rental price ratio is low now, what happens if I sell my house? When can I buy a house again? Since we are at a historical peak, should I just live on rent from now on? Considering that the rental system itself is likely to disappear in the future, is it even valid to use the rental price ratio as an indicator? If there are still multi-homeowners surviving, the tax environment has become so hostile that they can't pass all the costs onto rent, so they might decide to sell regardless of the rental price ratio. However, planning to buy a house based on the rental price ratio, like a smart single property investment, feels like a story from a bygone era.