This is not just an ordinary accomodation, this is a real adventure of living in wooden house in a very center of ancient neighborhood. You will have a great terase, a room with a monastery wall, and a bathroom in a room of ancient Turkish bath. The area is full of caffees, you can easily access to all the balat destinations. Mustafa and Mona were extremely welcoming, invited me for tea and told everything I need for comfort staying (Mona speaks Russian).
Transportation is ok, but a tram line to eminonu is under construction. But you will have ferry nearby. Anyway, this place is the best for exploring Balat. Muezzin singing can be pretty loud in the morning.
Consider this place if you want something unusual for a decent price. This is not 100% comfortable comparing to the ordinary flat (however the owners do their best to make it so). But it would be 100% remembered.