We spent 3 nights in Istanberry Dream Flats and we were more than satisfied with it. Güven was really welcoming and helpful, and the flat was perfectly clean and cozy, just like on the pictures.
first we had a hard time finding the place (the map& description Güner and Güven sent us was not perfectly clear neither for us nor for people we asked on the streets) but once we figured it out we realised it's really close to everything (main streets, Taxim square, etc).
they even offered us a flat with separate bedrooms on our second night but we were so happy with our place that we didn't want to move:)
I would highly recommend this place to anyone visiting Istanbul!