We had a really great week in Berlin and Sara’s flat was nicely located: close to public transport and supermarkets, great restaurants and cafes, and small boutiques or second hand shops.
The flat is as it is in the pictures, so we knew that the second room is small. My two daughters had no problems to share the bed (8-10) The backyard has a little playground, so my youngest could go down meanwhile I prepared breakfast, and we could watch her from the balcony.
We never met Sara in person, but Waheeb was super fast responding and fixing what was not working well (WiFi, and shower were fixed in less than 1 hour).
Definitely Berlin has a lot to offer also for children: the planetarium is 200m far away from the flat and had a great program for kids, the art museums have children programs on weekends, professional ballet in the opera house where kids do not pay (weekends afternoon and with explanations before the performance for the kids), the spy museum, the blue man group, the sees to swim on hot days, etc...and of course history, loads of history that you need to explain :)