This is a very important question thay has puzzled me for quite some time.
My block of flats has buzzers for each flat and then a ‘trade’ buzzer.
- The trade buzzer alerts all flats that someone wants in
- The trade buzzer magically opens the door for them rendering security pointless
- Something else
I ask because sometimes my buzzer buzzes when the postman wants in, sometimes it doesn’t. What gives?