I'm from Barcelona, and this was the perfect place to stay for a sightseeing weekend with foreign friends. You will be staying in a really nice, real neighborhood, with the metro one block away and enjoying the quiet environment this rooftop offers. Is like having a summer house in the middle of the city!
Andres was a delightful host and made us feel very welcome. Our flight was delayed and we arrived 2+ hours later than expected, but that wasn't a problem at all, and he waited for us until we got there.
If you want to feel like a real Barcelona citizen and enjoy some sunny breakfast in a rooftop terrace, I wouldn't hesitate but to choose Andres place!