I stayed at Başak's flat during my trip to Istanbul. It's in walking distance of main sights of Beyoğlu like museums and Galata tower, also from Taksim square and İstiklal street which are the main transport hub and a main shopping street retrospectively. Also you can easily walk to the cultural centre of Istanbul from there or you can always take a tram. The flat itself is clean, nice and cozy. Başak is really great host, she provides necessities like drinking water and is answering questions very quickly. The neighborhood is well lit and safe to be into even after dark in case you need to check-out early in the morning or at night.