The apartment I rented was on a quiet residential street about a 15-20 minute walk from Plaza Cataluña. It was small, but felt spacious and airy as it is well designed. The air conditioning was very efficient at keeping he summer heat at bay.
The listing is managed by a serviced apartment company which I gathered is quite large. They are neither particularly friendly, nor efficient. The lift was broken when we arrived, and walking up 6 flights of stairs to the attic flat was quite the workout. They did manage to fix it in the afternoon of the last day. Also, there was no welcome basket as the pictures suggest.
We also used the safe, as advised, but the instructions were confusing and we managed to lock our belongings inside and were unable to retrieve them. It took them more than a day to come by to unlock the safe.
During all of this, Arina was very professional and pleasant and responsive, so I fault the service she's contracted.
Aside from that, the flat could use some minor maintenance, but nothing major. The only part of the flat which I found objectionable was the state of the linens and the bedspread, which had cigarette burn holes and other stains. The linens were corse, and had orange seams (like hospital linens).
We paid £230 or so a night, which in retrospect was too much given all of the above.