How and when is it necessary to hang an announcement about video surveillance?

Question

CCTV

If we are talking about the hallway in our house and incoming guests, is such a sign necessary or not?
upd. The house is multi-apartment. Country - RF.

Answer 1

1 which country?
2 which house, multi-apartment (more than 3 apartments)?

Answer 2

If it is only inside your apartment - nothing is needed. Your property.
If it is common property, a sign is needed, it is desirable that the camera looks at it. (if it is removed after the fact of damage, so that it can be seen on the record)

Answer 3

Legal aspects of video surveillance: how to avoid ... (comments are just as interesting!)