Lovely apartment south of checkpoint Charlie in Kreuzberg. The neighborhood is hip and quiet, with closeby places to eat as well as metro, although I biked everywhere.
Babett/Stephan was in constant touch with us, very easy to work with, and very kindly let us check in early when our flight was changed to an earlier time.
Would highly recommend it if you're looking for a charming, beautiful place to stay in a quiet neighborhood!