We stayed at Aylin’s place for one month and were very satisfied. We were personally met at check-in and treated with warm hospitality, and also at check-out. The apartment itself is on a little side street, so it was very quiet, especially at night. It was also pleasantly cool, even though it was summer, I guess because the walls of the building are so thick. We never felt that we needed air conditioning. The living room has a huge TV with ten or more English-language news channels, and the wifi was good (but doesn't extend well into the bedroom, maybe due to the thick walls). The kitchen is well equipped, better than just about any other AirBnB we’ve stayed at. Lots of dishes, pots and pans, coffee maker, electric kettle, etc., etc. And the whole apartment was very clean.
After a month of exploring Istanbul, I'd have to say the location of the apartment is almost perfect. And if you are into walking, like us, you can ramble on foot just about everywhere. To travel further afield, Taksin Metro station and Sishane Metro station are both about 10-15 minutes walk away, and buses and taxis are no more than two or three minutes away, on the nearby main street. The ferry that goes along the Golden Horn, across to the Old City and across to the Asian side is also an easy walk.
There are LOTS of restaurants, cafes, bakeries, fruit and vegetable shops, etc., etc., nearby, so finding food is not a problem. For supermarkets, there is both a Sok and a Carrefour (two popular supermarket chains in Istanbul) less than five minutes’ walk away.
On a more esoteric note, if you are a jogger (like my wife), there is a nice park, Haciahmet Cinderesi Park, nearby that has a decent-sized jogging circuit, plus a lot of outdoor exercise equipment. Places to jog are few and far between in Istanbul!