The host was friendly and communicative although he couldn't give us any good advices on which places to visit in the city or good restaurants to eat (as he is himself an owner of one)
Anyway as for the room, it was more dusty than it should, the bathroom sink, toilet and shower were not very clean and we had to take a small box of chlorine and clean them ourselves in order to use them. The location was OK but not perfect because you had to walk uphill 400-500 to reach the main roads which lead to the sightseeing and the markets (with no mean of transportation up until that point)
Overall, it was our first time in the city and we didn't really know where it would be better to stay, but the next time i will spend 10-20€ more per night to stay somewhere more in the center of the eminonu area and in a more cleaner apartment.
I would give 2.5/5