I stay at Kerem's apartment for 3 nights with a friend of mine. Kerem is a top host. He has assisted us quite a bit as it was my first time in Istanbul. Every question I had was answered promptly and Kerem always went the extra mile to help us out.
One example of Kerem's hospitality and going the extra mile jumps out. My friend and I got a little lost trying to find the apartment. Kerem offered to come pick us up and deliver us to the apartment. Kerem arrived shortly and gave us both a lift to the apartment.
The apartment itself is even bigger than it looks on pictures. It's got everything you need and it's in a very good location close to top places to visit in Istanbul. There is a taxi rank just down the street so you can always get a taxi at any time of day or night. There is also Uber of course or you can hail a taxi in the street. We haven't used public transport but the area is well connected to public transport too. Taksim is a short walk away so walking to most places is also an option.
In conclusion I highly recommend the apartment and the host.