The apartment's best asset is the location but by no means does this imply it lacks somewhere else. After 5 days in BCN I truly believe Gracia is the coolest neighbourhood by far; lively, full of bars, restaurants and shops but still giving you the live-as-a-local experience which I believe wouldn't be the case in Barri Gotic or El Born. Lots of supermarkets and convenience stores a stone throw away, 10 mins walk to Sagrada Familia, a short bus ride to Guell park and 5 mins walk to L4 line metro which gets you directly to the most interesting places. The apartment is stylish, fully equipped, and looks exactly as in the pictures. The only think to be aware of, is that it is in the 3rd floor instead of the 2nd. Although the floor is typically called Secondo, there is a mysterious mezzanine sort of thing, but still the same deal of stairs to climb.
I did not personally meet David but the communication was excellent and the responses quick. Highly recommended.