Marisa's place is just called Art Gallery Apartment, you can find it directly on Google map. The location is superb, walking distance to metro station and buses, also surroudding by countless restaurants, supermarket, pharmacies, etc.
The apt is in an old building but the room is very stylish and spacious, much better than pic shows. Bed is comfortable, entire house is clean. And there is also a rooftop platform at floor 5.
There is a very nice reception lady available between 9am - 2:30pm, she is very knowledgable about BCN and many usefil tips about the travelling and restaurants.
Overall, a very pleasant stay.