Really great apartment, everything was like on photos. Well equipped kitchen, fresh bedclothes, modern furniture. WiFi was fast and stable.
District is quite and not crowded, but there are several cafes and supermarkets. Tram station near home allowed us to reach centre of Berlin in 10-20 minutes.
Only issues are that courtyard is not so great as apartment and building is not soundproof, but these problems were not critical for us.
Nicola answered super fast and even so we booked apartment in less than 24h before check-in, everything was clean and ready for us. His associate gave as two pairs of keys and answered all questions.
Would like to stay again there, thank you Nicola!