Uninvited guests

Random npc sims and ghosts are coming uninvited to my apartment and start using my household stuff (for example playing instruments, turning on stereo etc). I don't ask to come over or invite in, they just appear randomly and it's annoying to stop my sim activity just to ask them to leave. About ghosts, they aren't relative to my household and i can't make them to leave at all.

When I locked the entrance door to household only then it stopped, but when I actually want to invite somebody over then there is going to be so much locking and unlocking