I stayed at Filin's apartment some days with my relatives and it was a great experience. Filin contact me some days before the arrival providing all needed pieces of information to reach the apartment, and finally she welcomed us to give a tour of the hous and some hints during the stay. the apartment is new, well equipped and clean with all needed stuff. It's very close to Marmaray station so it's easy to move to the hystorical center of Istanbul. nearby there are shops and a street market on thursdays.
we enjoyed our stay at Filin's apatment. For sure I'll return when visiting Istanbul in the future, so I recommand it.