I have just arrived at home after 3 weeks for work, in Madrid. I would easily recommend this room to anyone traveling to Madrid: Everything is perfect!
The location is perfect, several supermarkets/shops in the area and very close to the Prosperidad Metro Station. The room (and the bathroom!) was very clean, bright and comfortable. Guiomar is a very kind host. She explained me everything in the flat the day I arrived, She was very helpful throughout the stay.
Thank you Guiomar! I wish you all the best.