The apartment was comfortable, had a cool design, big, and well located (4 minutes walk to a tram station).
Dietrich was very nice, available for us at any time, and gave us a lot of important information to get around the neighborhood.
the location is not a touristic area, we felt it was a quiet and safe neighborhood. yet, not far from touristic spots (15-20 minutes by public transportation).
personal tip: be sure not to go on a public transportation without having a ticket!! do not take your time buying one.. we got a 60€ fine each! you can buy single ride tickets on the train, but a 7 day ticket is only available in big stations.
to sum up, if you want to experience Berlin like a local, this is a great place for you.