Our stay at Bernd and Katja's appartment was all we could wish for in a nice quite visit to Berlin. The appartment was cute, comfortable and very clean and well organized with all the necesseties one would need. The location was great, providing a nice quite refuge when we wanted to relax, and the advantage of being close enough to reach every place we wanted within a short tram/metro ride. To some locations we could even walk. Having access to wireless internet in the appatment made our stay even easier, allowing us to check up things "live". The appartment even stood up very nicely to the extremely hot weather we had surprisingly encountered, and offered a relatively cool place to hide from the uncommon summer heat.
Bernd and Katja provided excellent tips - thank you guys! - to what we could do around, and were happy to answer all our questions. We also enjoyed our discussion of current world events, and wish we had time for more such discussions.
Overall, we had a wonderful experience and would like to thank our hosts very much. We highly recommend the appartment and would surely return there if we had the chance.