It is a studio with all the required amenities for a comfortable stay. The kitchen was well equipped so we could properly prepare our meals. We stayed for a week so we didn't eat out all the time. The washer was excellent, with dryer function too which made it really convenient. All the cleaning supplies were provided.
Figure out the heater when you check in, it can get very cold because it's on the ground floor with cement floor and walls, bring house slipper. Keep the bathroom floor dry around the sink and toilet, the ventilation fan was too small to air out the bathroom. We got our laptop so we could watch something online during our downtime, the wifi was good; there was no tv.
Since Istanbul is the city with 7 hills, many places including this place is not recommended to those who can't walk much, unless you are planning to take taxi all the time. I can't imagine anyone not from istanbul can drive in most of the neighborhood either; the streets are narrow and there are many steep hills with cars parked haphazardly along the sides. There are 2 bus stops nearby but both require a fair bit of walking involving climb up and down hilly streets; we had quite a workout during the week.
Overall, focusing on the studio itself; it was adequate for what we're looking for. It was cozy and neat, nice to come back to after a long day out hiking around the city. There's many shops and café in the neighborhood itself which made wandering around pretty interesting.