Although Vitaly wasn't there, he arranged everything perfectly for my arrival, and regularly checked during the week to ensure eveything was ok ! Vitaly is very consciencious, and his room is very spacious, well decorated, and comfortable.
The apartment is 15mn walking from the Tier-Garten, 2mn away from a lot of supermarkets and places to eat, and 2-3minutes away from subway (U-bahn) and bus.
I highly recommend it !