My wife and I stayed here for one month.
The appartment has a really nice location: Taksim and Istiklal street are literally here, Bisiktas district is walkable and Fatih district is easy to go to by tram. Ferry station is also quite close to the place.
Regarding the life here, you can find everything relatively fast: supermarkets, cafes, bars etc.
A lot of lovely cats around Alev's place, you can feed them right from the living room window.
It is very quiet and peaceful, even though not really far from main streets. Although, the closest bar can get a little bit loud on Friday nights.
Alev is an awesome host, communicative, friendly and helpful. The accomodation is really homey, you feel comfortable and relaxed right away. We would totally recommend this place to stay in Istanbul.