A tiny but cozy place, despite not being in the center of the city it's quite easy to get to the heart of Madrid with the public transport - or a taxi (they're a bargain if you are used to Milan or London). The place fits two, but really gives its best for a solo traveller; it has everything you need.
The check-in is not that straightforward, but help is always there at whatspp length and the guys are really supportive. I'd recommend this for your next Madrid stay.