We were very satisfied with the apartment. The owner is very friendly, and helps with minor questions about Madrid. It also seemed fine that we were staying up late or coming/going late in the evening. The flat is very clean, and in a very good location – Metro is in 5 minutes, cafes and shop in 2 minutes and it is only about an hour of walk to the center, by one street. All in all it was a very good experience :)