The apartment was exactly as described. Space was comfortable, clean, and very well located. Galata Tower is right up the hill and Istikal is a short walk away. Topkapi, Hagia Sophia, Blue Mosque are within 20 minutes (walk + light rail). The ferry to the Asian side was 10 minutes away. Definitely get an istanbul Card, it grants easy access to the ferries, buses, and light rail.
The apartment itself was well air conditioned and pretty comfortable to live in. There can be some street noise on the weekends, but generally it's fairly quiet. The rooftop terrace is lovely and provides great views of Golden Horn. There are tables and a desk (for you digital nomads).
Lastly, but likely the most important. The staff was great! I stayed for a month and the apartment was cleaned weekly and I was able to get help with the most mundane of things via whatsapp or just walking into the office on the ground floor. There is a laundry access as well (you may want to bring some Tide Pods -- to wash the clothes, not to snack on -- the stores didn't really have travel sized detergents but it was cheap anyway) .