My stay was Tiziana was amazing.
The neighborhood she's in is incredibly charming, quiet, and has several good places to eat and get coffee (Spreegold became a staple for me) -- in addition to being close to public transport and within walking distance of museums and shopping areas. I could go on and on about how wonderful my stay was, but I just say this: much of the reason I loved my time in Berlin is, in part, due to staying with Tiziana.