We had a wonderful time in Kristen's apartment. It's lovely decorated, fully equipped and really well thought for a short stay in Berlin. Plus, it's far away from the street in a nice second courtyard, which means that it's completely silent! We woke up everyday to the birds singing... The area is great with a lot of bars and restaurants. The U Bahn and the tramway are just around the corner if you need them.
Kirsten was really welcoming, she waited for us until late since we had a late flight and gave us all the information we needed about Berlin, even by messages during our stay. Everything was perfect. If we come back to Berlin we will stay at her pace without any doubt!!