For the price of almost 70,- per night (including € 25,- Airbnb costs) you can get a also a nice hotel in Madrid, but if you want to feel at home and have the freedom to cook your own meals, then this apartment is definitely a worthy alternative. Yes, it's 8 stairs and 91 steps, but you might need that kind of damage control in a city where there are so many good restaurants and you get your tapas with every round of drinks you order.
The apartment is small but it has everything you need. Ulises provides 1 big towel, so you might want to buy detergent and use the washing machine. The bathroom is the smallest of small (who knew you could fit so many essentials in such a space) but the shower is hot and comfortable. My side of the bed was okay (left), the right side apparently not so. There are plenty of windows to let in fresh air after a warm day. The location is top notch! Plaza de Cascorro is in walking distance of Metrostation La Latina, Plaza Mayor, Lavapies and so many more. El Rastro is literally on your doorstep on Sundays.
Ulises was very flexible with the arrival and departure even a miscommunication (AM instead of PM) proved not to be a problem. He is also very friendly. We would definitely recommend this apartment to everyone who plans to visit Madrid (we would definitely recommend Madrid also).
We stayed 3 nights with 2 persons.