Hasan is a great host. He personally welcomed us, gave us the keys to the apartment and showed us around.
he was very helpful and explained to us how to get the transportation tickets and how to get around in Istanbul.
He even rented us a SIM card so we were ready to go right from the beginning. He also arranged the airport transport.
The apartment gets the job done. It is centrally located and close to all main attractions like Taksim Square and Istiklal Street and it is also close to public transportation. But keep in mind that the way to the apartment is uphill and about 9 minutes from the tram station.
The apartment could need some renovation since some furniture is a bit old, but all in all you do not need more. One plus point was that it has an air conditioner.
Overall, it was a great experience and a great stay.