We stayed at Mustafa's "Nice Flat with Galata Tower View" for five nights. Arrival was easy, took a taxi from the airport and had the driver call Mustafa for directions. Mustafa was not in town but had someone meet us at the apt with the keys, he even helped carry our heavy suitcases up one short and three long flights of stairs.
It's in a wonderful neighborhood from which it is easy to get everywhere else you want to go. We never cooked a big meal but the apartment had everything we needed - coffee maker, dishes, knives, silverware, bottleopener....all the things you take for granted but wish for big time when absent. Plenty of sounds - cars, cats, voices - float up from the street. We liked it but if you don't the windows close tightly and block almost all noise. The mattress is very comfortable if you like extra firm. There was always hot water in the shower and plenty of pressure. All in all we reccommend Mustafa's flat as your home base when visiting the amazing Istanbul.