I really liked the apartment !
It has lots of storage and is easy to navigate, in the middle of the gothic neighbourhood.
Many bars and restaurants are nearby, as well as convenience stores and librairies ! It really felt like home !
Alex is very very nice, she really is the best host you can have !
Only downside was how hot the apartment gets as I could only use the AC for 1h before it turned off by itself. Hopefully the apartment comes with a powerful fan.
I'd come back at Alex's to visit Barcelona for sure !