We loved our stay here :) Very nice people, caring and helpful. Arda fixed the few tiny problems we had very quickly, and Irmak supported us remotely and prepared a small guide about the stores, restaurants, and other things in the area.
The location is just fantastic, I can't stress this enough. It's very close to the waterfront, bus and Marmaray stops, and ferries. A lot of opportunities to run, walk around, and watch the sunset—and cats ;) The area in the immediate vicinity is rather busy but step a few blocks from the Bagdat Cd and you're walking in a very quiet neighborhood. And there's everything you need for living, with venues for every budget and taste. (Hint: We loved Anzelem Et Kebap for soups and meat, look it up, it's like 800 meters away from the apt).
The apartment itself is nice as well, very spacious, with everything you need for longer stays: the kitchen is fully equipped, the knives are sharp, there are high-quality utensils, lots of dishwares, etc. They got a big screen and great chairs. The beds are great. There's a big table where we could both work and eat. And it's quiet! The main entrance to the building is on Badgat Cd. but the apartment windows look the other way and it's quiet.
10/10 overall, highly recommended for monthly stays :)