Pros:
— Location is very good, in the middle of very creative and beautiful district. There are many bars, sightseeings and activities nearby
— Apartment is cozy and has everything you need to sleep, cook, take shower and so on.
— Heaters — if you go on winter, it's a big plus
Cons:
— Price could be better, although it depends on your own expectations)
— The main thing — it's a basement floor. The down stairs are pretty high-angled and tight. Sunlight goes through windows, but they definitely could be larger, and looking at someone's legs is not the best view in the world)
— Another sensitive thing: as this is a basement floor, pretty strong specific smells from famous Istanbul cats are pretty much clear, especially after rain. I can't say it's a real problem, but be advised.
Generally speaking, this place is good to stay, but better keep in mind some specific things, to avoid bad experience.