Sergio is one of the best and friendliest hosts I've experienced through Airbnb. He gave us wonderful tips and suggestions on what to see and do in Barcelona.
The apartment was very comfortable in a great location.
The biggest issue I would note is that the bedrooms are not fully enclosed as they do not have doors. It wasn't a big issue, but it wasn't preferable.
Otherwise our stay was excellent and I couldn't recommend Sergio enough to be your host. His advice will ensure a wonderful time in Barcelona; especially if it's your first visit!