If your are traveling in a city that you have never been before, location and host are the two major factors. Fortunately, I've booked this nice apartment. Extremely closing to the Metro station which means you can visit every place in Madrid. As for the hostess Ursula, treating us as one of her family's member, she is the most enthusiastic and friendly women that I've ever seen. This summer in Madrid is abnormally hot, too hard for people to fall asleep in the night by staying in a room without windows, but Ursula tried out all the means to make us escaping away from this heat, even helping us move in other apartment which is more comfortable.
This is the best place for you in Madrid!