First I want to say that Hazal's apartment is more like a holiday flat. Nobody lives there. Keep that in mind if you're looking for an Airbnb, that is like an Airbnb used to be some years ago. If that doesn't matter to you, then Hazal's apartment is good.
It's situated close to the cool and charming quarter of Gracia and not far away from the Sagrada Familia.
Communication with Hazal was really good and fast, an agency took over at some point and managed the check-in, while Hazal was out of town.
Check-in was good and friendly, there were some snacks and lots of good tips for food, bars, etc..
Overall it was a nice stay at the apartment I can recommend it.