That's a slightly messy answer since it causes the lot slots to be used up. The Ingelogical shrub leaves attributal garbage on objects causing their costs to become corrupted. The "clean" way to do it is to backup the lot file, then after you move out, revisit it in build mode, save it, quit, and restore it back.
Why is it necessary to revisit it in build mode and save it? What I've been doing is moving the new family in, saving, then going out the game and replacing the lot with the previously saved one (with the furnishings intact). Sounds more sensible your way actually, that way they have to pay full price instead of getting a freebie. Not sure why you need to do the build mode part first, though?