If this place is available on the days you want to come to Madrid, BOOK IT NOW.
Everything about this place was outstanding. The location is 30 minutes from the airport (via train - very convenient), walking distance to the major avenue and if you're like me, walking distance to everywhere. I walked from the flat to Parque de El Retiro (20 minutes one way) and found the apartment to be a great place to unwind and relax after a long day. The apartment is impeccably designed and very clean. She cleaned the apartment on Sunday morning while I was sleeping and I didn't hear a peep or smelled any harsh chemicals.
Her kitchen was free range to make the tradicional breakfast of bread with olive oil and tomatoes and made sure there was other things to munch on at my leisure.
Now, to the important part: Claudia. I strongly believe she is the best AirBnB host I've ever had. The airline lost my luggage and she was sympathetic and allowed me to utilize her phone number so incase they found it, they would call her to arrange a delivery. When they did find it, she contacted me right away since I wasn't home to update me and assured me she will receive the luggage for me if I'm not there. Claudia gave many tips and answered my questions by suggesting places to go and things to see.
Madrid was a magical city for me and I will return soon, and without a doubt, book this flat over and over again.