We had a wonderful stay at Javier's place. The flat is incredibly clean, the bed comfortable, and it's close to several metro stations. We enjoy walking, so we went sightseeing by foot (including parc Guell and Barceloneta). It was very quiet too (on the top floor), and with earplugs at night, you can't hear the elevator noise at all.
For a quick bite late at night, carrer Blai is just 10min by foot from the flat.
Perfect.