To begin you are at the heart of the old city really at the heart.
Blue mosque, Hagia Sophia and the rest of old city literally 5 min. Sea front for evening walks when you have had too much delicious food 2 min. Two supermarket in 2 min walking distance for your needs. Historic Mosques that were built centuries ago the area is full of them. Throw a stone and you will hit a historic building. The North side of Istanbul across the water is 30 min walk, in fact we regularly walked from the flat to Taksim Square and got a taxi back. The flat should realistically house 4 people which makes it super cheap we only had two tho. You have Internet, toaster, microwave, oven gas hob, hair dryer, ample storage, washing Mechine in the basement (but ask permission). With all this available I forgot the flat had a roof top seating area. When I comeback to Istanbul I know where I will be staying :). The host also very nice and helpful.