We really enjoyed our time in Istanbul, made greater by staying here. The location is phenomenal, there are more cafes, bars, restaurants, antique shops - you name it - within walking distance, than you could cover in a year. The apartment itself is very spacious, with an excellent cross breeze in the living/dining areas, and AC in the bedrooms at night. The two bedrooms have ensuites. One faces the road and is definitely loud at night as "doof doof heads" drive past. The other is wonderfully quiet.
The place itself could do with a renovation - there's some cracks and bubbles in the paintwork, and the floor is quite squeaky, but we were fine with it given the historic nature of the building. If you're in Istanbul for the food, drink, and culture like we were, you'd definitely love this place, and its excellent location. I recommend a coffee shop called Gramaj a short walk from the apartment. They are masters of specialty coffee and serve a great Kahvalti (Turkish breakfast).