The apartment of Marta and Enrique was very nice, clean and well equipped with quite new furniture. It was also very well situated, in the middle of all down town activities of Madrid. On the other hand, this was also a drawback since windows facing the street, the apartment was very noisy in the evenings and late to the night.
In brief, in my opinion the apartment is nice for a short visit, but for a longer one like mine (about 2 weeks) the street noise starts to bother.