The best part about this place is its wonderfully central location in the historic Gracia neighborhood: A Metro station is just around the corner from the apartment building, there are tons of shops and restaurants nearby, and it's also within a few minutes' walking distance of major sights like La Sagrada Familia and shopping on the Diagonal.
The apartment itself has a very spacious balcony with lovely views of the city--the top feature by far! On the inside, the apartment is a rather compact 2-bedroom unit, but there were just two of us, so we stayed comfortably in it. We would note that the bathroom and its shower are small, and the kitchen is on the small side but fully stocked. The unit also includes a working washing machine. The building overall feels secure with an outer locked door as well.
Sandra also is a good and very communicative host--she immediately answered questions and responded to all requests we had.
Overall, if you need a very well located and solidly functional place to stay, we would recommend this place: You really feel as if you are living Barcelona, with easy access to all of the key things to see and do!