Me and my partner stayed for 3 nights at Alfredo's. The only inconvenience was no elevator and 4th floor.
The apartment was perfect for two people, comfortable, clean, and equiped with a small two place stove. The room is dark and you can sleep in and the mattress is comfortable. The kitchenette is small, but for two people, think cosy.
Alfredo was very nice to us, he was at the apartment to welcome us, showed how everything worked and told us to message him if we needed anything. He again met us at check out.
All in all, if you plan on going to Madrid to visit the city, you will get a nice apartment just 20 min on foot from Retiro and museums, 5 min from Gran Vía and a Carrefour just around the corner.
If you plan on staying longer and anticipate wanting to stay indoors, you have the TV with Netflix.
It is a good apartment for a visit to the city.
Thank you Alfredo!