Overall we were extremely satisfied with the stay: Mustafa and Ugur were very helpful and the apartment covered all our needs.
The apartment is on top of its own authenticity located in a genuine turkish neighbourhood and therefore perfect for travellers looking for a sight of the local life. It is in a decent walking distance from the old town or five minutes by bus - you really should try to create an overview of the public transport in the first days as it will make your stay in Istanbul much easier.
The terrace is very cozy and gives a wonderful view of the city and the local area which offers many cozy cafés and restaurants, small shops and a beautiful walk by the Golden Horn strait.
Mustafa who is the go-to guy is very nice however he only speaks Turkish and Italian but it is not a problem as Ugur , the administrator, is very competent and will answer any questions you might have and help with the communication with Mustafa.