We had the best time at Sinem's and it was perfect for our three-day trip to Istanbul. It's incredibly homely, has everything you need and it's located in a lovely area near lots of nice shops and attractions (Galata Tower for example). We even walked to Hagia Sophia and The Blue Mosque with no issue. It's also very close to some other great areas (Cihangir) where there are lots of places to eat and drink. Sinem was always quick to communicate and check-in and check-out were seamless. Would definitely recommend :)