It's a great place with a stunning view from the roof terrace.
The house is huge and there is enough place for everyone: 4 floors + roof terrace. You'll have your private elevator inside the house, pool table, and a lot of bathrooms :)
The hosts were friendly and quickly answered all our questions. The only problem was with the washing machine, it was old and didn't work. But I guess they will fix it :)
The location is also great. It takes 5 min walking up the hill to reach Istiklal the main pedestrian street in Istanbul.