Tiny and generally nice apartment in the heart of Madrid.
Ana was very communicative with us until the moment of our arrival. However, since then we have not received any feedback from her even if we asked her to re-send us the WIFI password. The apartment is cosy and fully equipped. When we arrived was quite cold in the rooms, but later on (i.e. next morning) the heating system did the job very well. The kids were very very happy with the bunk beds, even if their room was tiny.
The main problem we encountered was in the main bedroom, where it was a water infiltration in the wall and the wall was almost falling a part. I believe this could be a serious health and safety issue. We could also smell in the air the water mixed with the plaster.
During the night, in the main bedroom we could hear very well the noise from the street, including the garbage collector in the morning. However, this should not be a problem if you are hanging all night. Also you should have patience with the key from the master entrance in the block as you need to learn the trick to open it. In the morning we had great breakfast across the street. Also, in the evening there are great restaurants in the area with reasonable prices.