What should be done about the mezuzot (internal and external) when selling one's house...
- to a non-Jew?
- to a non-observant Jew?
- to an observant Jew?
To a non-Jew: take them down.
To a Jew: you're supposed to leave them up, and you can charge him for the cost. . There are differing opinions whether, if you have super-special mezuzas up there, you can replace them with ordinary mezuzahs; what I've heard is mostly that it's permissible. look in אשל אברהם he says you may change it to other kosher not so mehuder