We stayed in Carmen's apartment for 2 nights in Madrid. Her son had greeted us when we arrived and was very helpful in explaining about the apartment etc. The location of the apartment is superb, right next to Atocha station and very accessible to the Renfe lines and the Metro lines. The apartment was slightly small but very comfortable. There was also a few bars downstairs and a supermarket 2 blocks down. Overall a good choice for Madrid especially if u are zipping in and out to other cities like we did.