Martin was very nice as a host even though I messaged him the day before telling him what time we would be there and the apartment wasn't ready on arrival but that was ok because we went to alexanderplatz shopping square which is a 15-20 min walk or easy train ride metro across the road.
The apartment was as pictured nice, open and clean and good to relax in on the first floor so no stairs to climb up.
We couldn't figure out how the tv worked and when we messages martin he did not reply. The tv also didn't get any reception so we couldn't watch it anyway. And we couldn't get the sink to drain in the bathroom. Also the plates and utensils weren't very clean but that could be easily fixed. It was also in walking distance of the Berliner Dom one of the main sites in berlin.