I stayed at Sergio's place for a week. It is nice to stay outside the city center. You are within walking distance of Park Guell. I also did some walks in the neighborhood, e.g. Parc del Guinardó. The flat was very clean. I got all the instructions of the place well in time and when I had extra questions, Sergio answered immediately. Recommended if you want to stay outside the city center. At walking distance there is a metro and bus line, so you can easily visit all the things you want to :-).