The location is great. A metro station is around the corner and Atocha train station is a walking distance away. The area is fairly lively but the noise won't bother you as the apartment is not facing the street.
The apartment has all the essentials and is quite clean. We were staying there during the European heat wave in June-July 2019 and never had to turn the AC, it's fairly cool inside at all times. There are no windows and the apartment is poorly ventilated, so if you are humidity-sensitive you'd likely not feel comfortable in here.
Neighbors on higher floors hang their clothes to dry right above the entrance door and bedroom "window", which was a bit annoying.
There's a good bakery across the street.
I cannot recall an AirBnB check-in later than this (well in the afternoon), although the cleaning lady who let us in early was super nice and forgiving to my basic Spanish.
If you don't plan to spend much time inside, not humidity-sensitive and would prefer a very cool (as in temperature) place, this is a very reasonably priced option in central Madrid.