I rented this apartment for my mom and my brother. They loved everything about it and they didn't have any problems with anything. just in the beginning, when they first approached the building , getting in was a bit of work. they followed all the instructions but the door was not opening. but it only took 5 minutes, not more and after this they never had problem getting in. if you travel outside of EU make sure you have internet in your cellphone. you will need it to open the doors. Otherwise probably the best way would be to contact the host. the location is great, just 5 minutes away from Las Ramblas, Gothic quarter and the port. I was communicating with the hosts. they are very friendly and responsive almost immediately. Apartment is only for two people so keep that in mind.
I want to say thank you to the hosts and tell everone else it's a great place to stay.