Sefa's place is a beautiful quiet oasis in the middle of bustling Istanbul. The apartment is located only minutes from Taksim and Tophane and is decorated in a lovely, quirky way (the pictures of the interior doesn't do it justice).
Upon our arrival the apartment was easy to find, and Sefa was waiting for us patiently even though we had been delayed getting out of the airport. The apartment is located on the top floor with no elevator, however, meaning that carrying luggage up four flights of stairs is required. (On the other hand, all of Istanbul is on hills, so you have to be used to walking up and down.) The studio apartment has a kitchen, a living room, and a bedroom, as well as a bathroom with a spacious shower. The balcony has a nice view of the rooftops and is a lovely place to eat breakfast before exploring the city. Due to being on the top floor and a few streets away from any main streets, the apartment is also surprisingly quiet, and so we had absolutely no problem getting a good night's sleep.
Overall, we felt very much at home in Sefa's apartment and loved our stay in Istanbul. If and when we return, we would definitely book his place once again for both the location and comfort.
P.S. Just a note about the air conditioner: We were told upon arrival that the excess water from the AC needs to be emptied, but, (due to a minor language barrier) we were not aware of how often. We found that if the AC was on for 7–10 h (e.g. during the night) the excess water would need to be emptied before it would start to drip from the AC. So if you have the AC on, do remember to pour out the water ever so often, and don't leave the AC on when you're not in the apartment in case it begins to drip on the floor.