I traveled with my boyfriend to Madrid late May 2014 and stayed at Fernando's apartment for two nights. Fernando was very quick in getting back to us before our trip there and it was easy communicating with him. The location of the studio is easily the beast part about the apartment. It is a few minutes walk from Callao and Sol. Very close to all the shopping streets, the plazas and restaurants. Fernando suggested a few places for eating and shopping and that as quite helpful.
The studio itself is comfortable for two people and my only issue was with the windows. So there are windows but they open into a small area in the middle of the apartment complex , so there isn't any breeze. And at night when you leave the windows tilted , you can smell the food getting cooked in the nearby apartments which is not so nice. But since there aren't any windows opening into the street , it is quiet. We didn't meet Fernando during the trip and his housekeeper handled our check-in and check out. Rosa Maria, his housekeeper is very nice but unfortunately doesn't speak any English , which was a bit of a challenge for us.
Other than that our stay was quite comfortable.