Sara is a really wonderful host and I'd definitely recommend her apartment if you're passing through Madrid. We loved its proximity to the Puerta Atocha train station, which made inter-country travel significantly easier. Her place is near the city's best museums (Reina Sofia, Prado, others) and the Parque Retiro. It was easy for us to walk everywhere we wanted to go during our stay, which was a big plus for us. We had some key/lock troubles at one point and were really amazed at how quickly Sara remedied the situation - she's great. And since I speak only a small amount of very poor Spanish, it was nice that she (and her sister, who met us initially) both spoke great English. We felt very welcomed.

Although Sara allows smoking (somehow I missed this