The layout of the apartment wonderful as you have your own private space which is spacious.
You must be ok with pets, the cats were lovely! Couldn't stop playing with them!
Location is great, be prepared to walk as Barcelona is a walking city and best to book Gaudi tickets online in advance. However at night due to the locality of the apartment you do hear passerbys, if you don't mind a little bit of human traffic in the evenings then it's fine.
The room is spacious with a living area and double bed. Christophe is a wonderful host! Definitely worth a stay if you're in Barcelona.