We enjoyed our stay at Gurubish's place. The best way I can describe this place... a rental of a Turkish apartment in a Turkish neighborhood. For us, it added to the adventure of exploring Istanbul.
Pros - the view from the roof was amazing (we enjoyed sunsets each night overlooking the city), the owner accommodated a very late check-in (2 am), plenty of space for 5 people, a well-serviced apartment, and a washer and dryer in the unit helped us catch up on laundry as this was a stop in the middle of our travels
Cons - internet happened to be out when we were there (the owner checked and reported the problem to the internet provider) but it made it hard to research things, location was as described but added at least 10 minutes to our walk each way to the sites.