Amazing stay! Stayed at Belgin's place with my parents for a full week. The duplex is especially great if you're travelling with 3-4 people but still want some privacy in the evening. The apartment is easy to find, clean, has two airco sets which is a must for the heavy Turkish heat, fully equiped kitchen and nice bathrooms. Communications with Belgin went through the Airbnb app and Whatsapp, which was fast, flexible and easy.
The apartment is located opposite of a taxi kiosk with friendly people willing to bring you to popular Istanbul hotspots for a low price. Just be mindful of the fact that traffic in Istanbul gets awful during the day so best to plan accordingly. Alternatively there is a busstop ~10min from the apartment with buses bringing you to the central parts of Istanbul. The walk is a bit uphill, maybe to take into account accordingly.
There is also a Carrefour S.A. located ~10min from the Apartment which has everything you need. Next to the carrefour are also some nice restaurants. Again, the walk to the Carrefour is uphill, so best to take this into account.
Check-in and check-out went smoothly, and Belgin was so kind to check-up on us during our late check-in to make sure we arrived safely.
All in all, a great stay for an amazing price!