Fatma and her husband are nice people and their daughter answered in English very quickly to our messages. They arranged for us a pick up at the airport, which was very nice and convenient. The location is close to Istikklal and Taksim, so it is a very convenient location in Istanbul. But we have to say that there were a few issues.

The flat is a basement, so there isn't much natural light coming through the windows, and moreover, we had to keep the curtains closed all the time, as there were various men sitting right against the windows, almost 24 hours a day (seriously, they were only away around lunch time), and during all our stay (9 days). They didn't bother us when going in and out, but they were sometimes quite noisy at night, talking, shouting, listening to radio, or playing with scooters, so it's not recommended if you are a light sleeper.
We wouldn't advice a girl to stay alone in this neighborhood, as our istanbul friends told us that this area, known as Tarlabasi, isn't very safe at night. It is certainly an opportunity to live in an authentic popular area, but although we came various times in Istanbul, in this particular neighborhood we didn't feel relaxed.

The second point is that the flat is quite humid, there was mold on the walls in the bedroom, and there was a strong smell of mold too. The smell improved when opening the windows, but for the reason explained above we seldom opened the bedroom's window, because it gave us the feeling the men were inside the room... Opening the windows in the kitchen side helped a bit.