If you don't mind small spaces, this is the best choice in Istanbul.
It is packed with every possible amenity - from washing machine to hair dryer to liquid soap.
It is well lit, has amazing wifi and is super comfortable to work in.
The wardrobe is spacious and the bed is comfy.
The location is absolutely the best you could find in Istanbul.
I will definitely be back and highly recommend it to every single person on the planet.