Overall, we really liked the apartment. The location is subjectively in Barcelona's best district - Gracia.
The apartment is a bit smaller than it appears in the pictures, but you get a balcony + decent rooftop terrace.
One thing that bothered us is that apartment was missing some basic items, like garbage bags or additional toilet paper, so we had to buy a few things ourselves.
We were also missing a few towels, but the support team was very helpful and solved that issue for us very quickly.
If you are a small group of people visiting Barcelona, I can only recommend this flat!