Nina and Soren were very helpful and very approachable. The information they gave us regarding Berlin, things to see and also the check in process was great. We had no problems and really enjoyed our stay.
The apartment is fantastic. Lots of space, a really nice quiet area and very close to two U-bahn stations with easy access to the city.
The kitchen has everything you need (even a collection of herbs and spices!) and little touches like having shampoo/shower gel was fantastic (especially as we arrived on Sunday and everywhere was closed!)
We had a really great time and would recommend Soren and Nina and their apartment to anyone to enjoy a great time in Berlin.