This is an excellent choice for a stay in Madrid. I spent 8 days here and was thoroughly satisfied with my decision. I arrived a little earlier than expected and Daniel arranged for a friend to check me in. But it was not a makeshift check-in, his friend could fully brief me on the apartment and any of my questions. Daniel was also in touch to ensure all was well.
The apartment has everything you could need. Although compact it is well appointed. I found the bed a little soft for my liking, but that's a personal choice. There's nothing that detracts from the value, utility and convenience of the apartment or its location. He also, most generously, stocked the kitchen with breakfast goodies.
Highly recommended.