Aureo's apartment was a very big surprise in very different points. Honestly, I wouldn't recommend it to a friend and I will explain with details my reasons. However, if you want a place with easy location and cheap price, that apartment can work for you.

First of all, I want to reinforce that I am used of it staying on AiBnb places while traveling and I was aware it would be a simple and cheap place.

On the other hand, I was not informed about a flea market that takes place on the street on Sundays and turns the neighborhood into a dirty and strange place. I was also surprised with the bad conditions that the apartment is when it comes to conservation:
-The main door is partly "rotten" and this gave me an insecurity sensation (after some days I realized the neighborhood and the building is safe and calm)
-all the furniture is old
- there are some walls with mold (including the wall where the bed lies)
-he (the owner) keeps some old stuff and leftovers (such as old objects and magazines) in the house
-the towels were smelly
-the bathroom door knob is broken so it doesn't close properly
-there is, for instance, a frame on the wall with a broken glass.

Of course these are only details but they matter when they are together.

Positive aspects:

-Aureo tried to understand my reasons when I contacted him. Although he was not able to cancel the reservation( and I really see this is businesd) when I tried to find another place to stay, he was really helpful during all the time
- walking distance from a lot of nice places in Madrid (including three or four different subway stations)
-supermarket an bars around
-good shower
-very fast internet connection