A very good pod to explore amazing Istanbul from!
The listing itself looks pretty much like the pictures – nice & clean furnishing. It's noteworthy that the upper floor (living room & kitchen) is on street level, and the lower floor (lounge, bathroom, bedroom) are on the basement level. The bedroom however has a skylight, so no dungeon vibes. :) Also, one has to mention that the WiFi is very strong, and the door/building well-secured.
Also, as others have noted, it's located on a pretty steep street; however, the entire area is a collection of steep streets, so if you're averse to that, you might want to look somewhere less close to the sea. Nice sea views from the street level are the rewards, though – as well as proximity to great food places (definitely try Vegan Food Cartel (lunch/snack), Norm Coffee (coffee) and Doğacıyız Gourmet (big Turkish breakfast) and Istiklal, Taksim, tram to Fatih (Blue Mosque, Ayasofia etc.), ferry to Kadıköy etc.!
Yıldıray and his colleague Mustafa in particular were really helpful, super responsive and immediately e.g. tended to a minor issue with the heating. Very professional!
Overall a very good experience that I'd recommend at a competitive rate!