I really enjoyed staying in Isabel's apartment. It was clean, cosy, provided everything that you might need and almost most importantly I consider the location to be most convenient. I wasn't so lucky with the weather though but thanks to the nice apartment I didn't mind spending a bit more time there then originally planned.
Isabel was very kind and helpful too. I would not hesitate to recommend her apartment to anyone looking for a authentic place to stay in Madrid. Thanks again and all the best from Berlin!