Trevor's apartment is precisely as advertised - great location, VERY well stocked with essentials for your stay (laundry pods, coffee, even two types of milk) and although not the largest place, it's very well designed and maximizes use of the space. Communication with him and his team was smooth and easy, we had a problem with the shower and he worked to address it and repair it quickly and efficiently. We traveled with our 1 year old daughter and really appreciated the toys and books, which were hugely helpful in keeping her busy during the day.
The only thing that could be improved are the pillows, which made it quite difficult to sleep as they seem to have been in use for quite some time and are worn out and not at all comfortable. I ended up using the throw pillows from the couch to sleep which was less than ideal
Overall, we had a very good stay and would definitely recommend this to families who want to be central to ALL of Barcelona's attraction, food, drinks, etc.