This is one of the best experiences I've had with an Airbnb host. Fati was a mine of information. His suggestions were much appreciated.
The apartment is central. Accessible by public transportation and taxis. It's walking distance from major attractions (2-3 minutes from Galata Tower; 30-35 minutes from Hagia Sofia). There are a lot of good restaurants in the neighborhood.
When we return to Istanbul, we'll probably try to book it again.