The flat was perfect for a short visit of Madrid, mainly for ths convenient location right next to the station (Atocha) which is actually also only a walking distance from the museums and the park, and if you're good on foot a walking distance to anywhere else. It was also very easy to access, they have a self check-in so that yoi can arrive at any time.
The flat itself is in an interesting building with a small patio with loads of laundry, and very clean. It is not the most cosy flat but has everything you need for one or two people, particularly if you are planning on using it mainly as base to visit Madrid.