I stayed at Natalia's place with two friends and it was perfect. It is on the fifth floor and there is not an elevator, but if you don't mind the climb it is well worth it. Natalia was a great host and was very friendly and helpful during check in. The apartment itself is the most beautiful I've stayed at using AirBnB, and has plenty of amenities to make your stay more comfortable. I would recommend this place to anyone and would stay again if I am ever in Berlin.