I don't know either.

Maybe it would become so common that it actually doesn't affect my decision making. I would want to save my bitcoin to have more money, but what is the point of saving it if I don't spend it? If btc purchasing power keeps increasing indefinitely (at least during my lifetime), I certainly wouldn't put off buying a house indefinitely. As many commenters have pointed out, I think the solution would probably be smaller houses and whatnot.