I am a burglar, I'd advise ringing a random number, if you get a reply then just claim to be the grandson of the old lady in flat number so-and-so, who's deaf and can't hear the bell, so could you please let me in. Works a treat, no one knows their neighbours, and, more importantly, no one gives a *beep* If you ring a bell and get no response, make a note of the number. That flat is empty, and so ripe for the picking. Either that or its inhabited by a deaf old lady, and those places can be burgled even when their at home. Win-win.
I live in South London in a small block (only 5 flats) and we have a communal door on the ground floor which is always open so any visitors can just walk straight in to each flats front door. There's no intercom system or anything but the building is from the 70's. Have to say I'm the only person I know whose flat has that setup.
I rented a nice flat this year (May) close to Chinatown. I believe there were three units stacked one upon the other. I had a code to enter from the street and a door key to the room. No bells or buzzers whatsoever. Also last two days some dog *beep* in the foyer. Enjoyed drinking beer on my second floor perch and watching the Chinese prostitutes working the street. Don't get me wrong. I love London and will return!
He killed sixteen Czechoslovakians. Guy was an interior decorator.