It is a room provided by the nearby Sur hotel, which we did not realize till we actually got there. So it was more like renting a hotel room rather than staying at the local's accommodation.
The room was spacious, modern, clean, fully equipped, location was great (7-10 minutes walk from SultanAhmet and so close to the main sights), cheap, and comfortable.
In terms of security, it seemed that the place was easy to break in, the locks were all like the bathroom door lock. That is almost the only thing we were worried staying at the place. (It has a safe although.)
There were small shops nearby where we could get basic things, from fruits to beer.
The surroundings were quite, sort of local environment, but on the other hand there were not so many people walking in the evening.
We could leave our language after we checked out, and we really appreciated it.

The one thing we were disappointed, was that we did not use the pick up service and the instruction to reach the place was rather vague and not well provided. I asked for a detailed information twice but it was still quite vague, and really at the last minute inquiry we received where we actually had to go first. (And it was too late since we did not have Wi-Fi.) But I assume that was the thing we should have confirmed precisely before starting the trip.

The check in and out wasconducted at the Sur Hotel, and it was really easy.
If the security was better, I would recommend this place to my friends.
We randomly met other airbnb user in front of the building, so we assume that several rooms of that apartment are owned by Saban. (BTW We did not actually meet Saban.)