Quim was so friendly and helpful when we showed up - the perfect host! His apartment was perfect for our seven people ( three couples and a single). It is clean and modern, comfortable and convenient. It is quite close to the Reina Sofia museum and the Prado with easy access to many, many good cafes, bars, restaurants, and shops. (Don't miss the Museo de Jamon).
If our group gets to return to Madrid, we would definitely stay here again!
Although on a busy street (easy access to cabs and Metro) the fifth floor location made it quite peaceful and quiet at night. The entrance halls were clean and well-lit; the keys worked fine; we were glad to use the small but efficient elevator. We were also glad of the in-room air conditioning units in this late August heat.
Our highest recommendation!