We arrived at the apartment and there was a little bit of a hiccup with the lock on the door but they immediately responded and sent someone out in a flash to help us out. They were extremely professional when it came to customer service.
The location is absolutely amazing. Besides the fact that it's right behind Casa Batllo you're on a main road that leads to all sorts of sights. We literally walked everywhere. The little bakery next door is also amazing, try everything!
We spent very little time in the actual apartment so the only complain we really had was that the towels had a bit of a smell but that wasn't a deal breaker.
This is really a fantastic place to stay and made our trip unforgettable, we highly recommend it!