Cristina's Airbnb is fabulous. While I only stayed for 1 night, it was a very comfortable stay. I had my own room with a very comfortable bed. The bathroom and kitchen is shared with Cristina. The shower had hot water and good water pressure. Both the bathroom and kitchen were fully stocked with all the essentials you need (including a hair dryer).
Cristina was a lovely host. She let me check-in early and leave my bags in the apartment while I went exploring. The apartment has an excellent location (about 5 minute walk or less from the Reina Sofia Museum). Also near lots of shops, restaurants, and only a short walk away from accessing the rest of Madrid!