Nida was a great host - she's a very pleasant woman who explain what to visit, when and how to get there.
About the apartment itself - we were in the Studio apartment, which is located in the basement. It looked really good and comfy, tea, coffee and water were provided.
However, there was a quite strong smell of mold and sewerage, so if you're going to spend a lot of time in the apartment and you have a sensitive nose like mine, specifically this apartment would be not the best choice.
All in all, a good value for money if you just need a place to crash/sleep in Istanbul not far from the centre.