This is a very cozy place for stay and centrally located to be convenient for exploring Madrid on foot. Caludia is very helpful and hospitable person. All essential amenities for home living are in place ( the big advantage over a hotel) and Claudia is always listening to help you with what else you need. I had a most comfortable living. Although on business, I found easy access to Retiro park and Reina Sofia museum very rewarding. Despite being in the heart of the city it is in a really quiet lane.
Two things to note for the older travellers : the apartment is duplex, with bedroom on lower floor and bathroom and kitchen upstairs. Secondly, Anton Martin and Lavapies metro are very close and Atocha also an easy walk. But the city is hilly so slopes are encountered, noticeable especially if luggage is heavy. Anton Martin does not seem to have escalators or ramps but Atocha is well set up. On the other hand taxis are available in plenty and are very reasonable and professional.