The apartment was lovely and clean, very central right beside the Brandenburg gate and the Holocaust memorial museum. It’s surroundings were quiet at night and we were right beside the u-Bahn which made commuting through the city easy. However check in wasn't smooth. Our flight was delayed and therefore we didn't arrive to the apartment until midnight. Due to this, keys were left in a key box in a different location to our apartment. Both were very difficult to find as this was our first time visiting Berlin, it was dark and there was nobody around. It was an uncomfortable experience.
The lift in the apartment also only reaches the 6th floor. The apartment is on the 7th floor. This was no problem for us as we could lift the bags but it is not the same for everyone. Overall, a nice stay.