I would like to thank Kemal and his team. Here are some pros/cons of the unit:
Pros: the house is spacious and in a great location, close to Galata tower/ Galata port/Istiklal street, .... In addition, it is a safe place. Easy check-in and check-out. A lot of windows where the sunlight can enter.
Cons: Kemal was not flexible with my family and me, and he asked to pay for a full day for an extra few hours because my flight was at night. Even my check-in was also late. The filters in the bathrooms are very dirty and need to be cleaned regularly. The mattresses must be replaced (noisy springs and muscle stiffness in the morning).
In overall, it is a great house, and I fully recommend it after fixing these minor things.