We spent 2,5 weeks in Dietrich's flat in July 2017. It was perfect for us for that amount of time. We even brought our little dog and she loved it there!
All communication with Dietrich was easy and he was very helpful. We arrive at the flat and we thought it was much bigger than the photos show :)
It's on a very quiet street and on the ground floor so it was easy to come and go.
We spent some time in Volkspark Friedrichshain (2 minutes away with a bike) which was really nice. You can jog or work out, have a bbq and just chill out there.
The flat is close to public transport and bars and restaurants. There's some really nice restaurants closeby too (Langosch, Xigon).