Try apartment No. 19

You try the door to apartment No. 19 but it doesn't budge, just as you expected. You hold your ear to the door, a strange low humming sound, emitted by something on the other side.

Perhaps the mail will reveal something about its occupants, dead or alive... Nope, it's all junk mail, addressed to a 'Soos Ané'. Well at least you got a name. Must be French or something, cause it has one of those funny 'E's'.

Either way, without a key or an alternative method of entering, you can't do much.