Stayed at Arda's place for a week. Arda met with me upon arrival and was extremely helpful to get oriented. It was clean and inviting with a great view of the Ataşehir Business District.
The apartment is essentially brand new and there are very few neighbours, so the place was really quiet. The local area had markets and restaurants within a 200m walk that were really convenient.
Watergarden is within walking distance and Metropol Istanbul is about a 10 minute taxi ride away. If you're a really savvy traveler or if you're too tired to cook, you can just order in with Getir.
Overall, the stay was amazing; I was able to get out and see all the sights and Arda's place was a great home base to see everything in the Ataşehir area.