We stayed in Henrik's studio apt for 3 nights and it couldn't have been better. It's a spacious room, warm and cosy (we stayed in a rather chilly October!). Separate bathroom with a piping hot shower and separate kitchen which is very well equipped for eating in if needed.
The area is quiet and relaxed - some gorgeous nearby cafes and parks, and a supermarket at the end of the road. 10min walk to alexanderplatz with shops/markets/cafes in the surrounding area. Subway nearby too.
Henrik was very good with keeping in touch pre our stay, gave us great directions, welcomed us in at 11pm (!) and gave us lots of tips. He was always available if needed.
All in all, this is a great place to stay in Berlin. Perfect area, great apt, privacy and a helpful host!