The place is very close from the subway/bus, and in a nice residential area with useful shops/restaurants/etc. The park of the Charlottenburg castle is just ten minutes walk away. I liked the China/India decoration of the flat. I recommend the restaurants "Himalaya" (indian, two blocks away) and "Saray" (persian, near the castle).
Note that the room is over a lively place, with restaurant terraces and a busy road. In summer, you cannot leave the windows open. Inside, it is quiet.
I also recommend you to be sure you have all the information needed before coming, the check-in was a bit difficult, there are non-obvious issues (such as the fact that the main door, near the subway entrance, is closed on Sundays and that the elevator needs the key that you do not yet have).