We had a great stay for a few days with our 2 children (3 and 7). Markus helped us on many occasions (even to find a dentist open on a saturday).
The flat is nice and perfectly clean, exactly like on the pictures. Location is not in Munich's center and not very lively, but you get to enjoy a quiet stay and we could get to the center in approx 25min in Straßenbahn, so a good combination overall.
Still expensive in general, but Munich is for some reason crazy expensive so this place is just no exception.