This is a professional listing as became clear by the elaborate information e-mail that was sent prior to our arrival. The owner also own the Istanbul360 restaurant.
The apartment is furnished by IKEA and thus doesn't really have any special charme - however, it was spotlessly clean. Also, there were some very useful information material and local tipps (i.e. on restaurants) in the flat, which was very welcome.

The main pain point was that the door in the shower was missing, such that the bathroom floor was always flooded after every shower. This was quite annoying. The water pressure also was not very satisfactory.
The floors are quite squeeky and you can hear everything throughout the apartment - consider this when traveling as a group.

We visited other friends in an AirBnB and thus discovered what else would have been possible with a similar price. Next time, I would look for an apartment that was actually lived in.

Overall, it was a great stay, but if you are looking for a flat with Turkish character you have to look elsewhere.