The space is very clean and comfortable. Checking in and out was easy. The AirBnb itself definitely feels spacious and luxurious. There was some water damage in the bathroom and in the bedroom ceiling but I’m confident the host will have it fixed by the time you book your stay.
The only thing to be mindful of is that your neighbors can be noisy both in the building and on the street. The upstairs bedroom is quiet, but the 1st floor bedroom is very loud with the wrong neighbors. If you are a very light sleeper, I would recommend you sleep in the upstairs bedroom, or stay in a quieter part of the city. I would also say that this part of the city is a great location for shopping (a lot of malls and food) but is a little more edgier than the fluffier more touristy Taksim Sq area. Think Times Square in New York.
Outside of that, I could not recommendi this place more! If you are a first timer in Istanbul, Mustafa is one of the best hosts you can get. He has great recommendations on things to do, and will get you around the city hassle free. He is great at booking excursions for you, and can have everything taken care of for you from the moment you walk out the door, till you arrive back home.