Very helpful and responsive host. He was gone during my stay so this was a 2 room apartment for the price of a room.
The building is perfectly located, very close to the tram station and 15 minutes by foot to Alexanderplatz. Equipped with everything you might need, great views, comfortable bed with black-out shades. The apartment must have gone through a small makeover and looks better than on pictures.
Key pick-up with the concierge didn't go so well but Martin promised to take care of this issue for the future.
Overall I highly recommend ;)