We stayed at Murat's place for 6 nights and it was absolutely ideal. Very well located in the middle of Kadikoy, a few minutes walk from the ferries, buses, etc, as well as the cafes and shops of Rasampasa and Cafaraga.
Murat's place had everything we needed for the week. It's a good size, two double beds, working hot water, etc.
We'd stay again!