The good - Pilar's apartment is very tastefully decorated, and both apartment and building have lots of character. Communication was fantastic. We needed help with a few things during our stay and everything was always resolved super quickly and efficiently. Great host! Location is nice, very close to the Sagrada Familia as well as to the L4 metro line. The flat was always warm enough as there was decent heating. Kitchen is very well equipped if you fancy cooking or making coffee.
The bad - only comment, you can't see it from the listing's pictures but the apartment is very long, and only the living room on one side and the master bedroom on the other, have windows facing outside. Two bedrooms, the kitchen and the dining area, all have small windows into a narrow dark inner courtyard, so they don't get any natural light. If you're never planning to be in the flat, it might not matter, but we might have reconsidered had we known beforehand.