Pros: Amazing location, communicative host, Juan got us a bottle of wine and some snacks too for our stay.
Biggest Con: Very noisy area (lots of noises coming from outside throughout the night and the neighbors were drilling the walls through the day)
Minor flaws: Some of the floor tiles were loose so they wiggled whenever you walked in the apartment, the stairs inside the apartment are very inconvenient especially when you get up in the middle of the night to go to the bathroom, the bathtub is like a hole in the ground so you have to be careful not to fall in it.
Overall we enjoyed our stay at Juan's place in Barcelona.