I couldn't recommand Arda's place more.
Hospitality, kindness and cultural exchanges in a very cozy and peaceful flat with a balcony directly on trees and gardens. In the district of Kadikoy, a little laid back from the crowded Istanbul center yet a lot of shops and nice bars/cafes around, and also not so far from the sea front.
One of the best Airbnb experiences I had lately, like it was back in the days, with humanity.