Carmen's place was pretty accessible from the Atocha train station - we had no trouble finding it. We were greeted by her son, who showed us to our room, which was pretty dingy, hot and didn't quite feel clean. The summers in Madrid are hot and humid, and this apartment had no air conditioning or fan, and the room had poor circulation. Similarly, the kitchen was pretty dirty. Although there was a corner where they kept coffees, teas and snacks for us. The tap water is potable, but my boyfriend didn't feel comfortable filling our water bottles in the sink because it was dirty. We purchased water bottles instead and were told we could use the fridge to cool them, however, when we took them out of the fridge the next morning, they had been drunk out of. Carmen is a very sweet woman and was great with us, but, unfortunately, we did not have a very good experience at her place.