For having a plecent stay in Berlin I blindly recommend Robert´s place. We stayed at his place for a short period of time, our trip to Berlin was mainly buisnes, but we got to see Berlin under the sun at the beginning of spring!
The location of the apartment is perfect for tourism, walking distance from the historical center, and close enough from the berlin nightlife so that you can go by foot but far enough so you wont be disturbed by the noise ;)
The apartment is beautiful, super clean and tidy, all that we needed for our stay was there + Robert gave us some tips for what to visit in Berlin and where to eat.
Easter egg- Waking up in front of the Zionskirche is an amazing and beautiful sight!