We stayed for 5 days in this apartment and it was great from the very first contact on. Sören cared a lot, was always nice and easy to reach.
The check-in went well and Sören not only prepared a little surprise in the fridge for us (which we happily enjoyed) but also told us about nearby stores, bars and restaurants.
The neighbourhood Charlottenburg is quiet and safe, there are grocery stores like Edeka, Lidl, Netto, Aldi and a shop that has open till night just around the corner. Public transportation is also in a walking distance (bus and subway).
The apartment itself is really charming, it has high ceilings and a country house style, which lets you feel very comfortable. Sören bought us extensions to the kitchen table, as we were 6 persons and also wanted to work with our laptops there. Speaking about this, the Wi-Fi is fast and works excellent.
We highly recommend Sören and his apartment if you want to have a nice stay in Berlin.