Mercedes apartment is really really nice. The bedroom is small, but nice and the bathroom is just fantastic. The apartment is in a perfect location, close to everything and the bus from/to the airport stops nearby.
I did not meet Mercedes in person because she was at work but her son let me in and showed me around.
The communication in advance was a bit difficult since I don't speak Spanish and Mercedes speaks only a little English. I also could not give the exact time of arrival in advance by email so I had to call on arrival. Anyway, in the end everything worked out perfect and I would definitely recommend staying at Mercedes' place.