Karsten is a really nice guy!
For longer stays this apartment has a bit of a small, unhandy kitchen.
For short stays or people who won't use the kitchen is might be a bit easier.
The noise from the tram is very very loud, but we heard the tram line is being stopped soon.
The shower is amazing!
Parking was relatively easy to find, and often right in front of the door if you are able to time it well.
Doing laundry was a bit far, and there was no equipment to either hang wet laundry to dry, or to hang shirts and other clothes (just a coat rack in the entrance).

We had a great time in berlin, and Karsten did not hesitate to offer us help in making our stay better.