In contemporary Russia, apartment survivors will have several extra problems. The entrance door with its electrical lock (without power door will be opened). Have you any idea how to fix this?
Russian Apartments Edit
It's unlikely that you will be able to successfully power an apartment with electricity. A small generator could be jerry-rigged to the door, but that's only a temporary solution at best. A simply barricade may work (a fridge jammed up against the door and leveraged against a wall. Alternately, a chain lock could be bought and affixed to the door. It's not something I'd want to have to do, though, while zombies are banging on the other side.