I traveled with 2 friends to Barcelona. Self check in was smooth, however we requested to check in 2 hours early or just leave our bags into the apartment (check in is at 3pm) and we weren't able to know if it was possible till the very last minute while we were in the taxi. We were granted that eventually.
The apartment is clean and looks the same as shown in the pictures, however the sofa bed didn't have bed linens on. We got them later on at night after requesting it since we needed one bed for each person.
At checkout we asked to leave our bags there after check out time, but it's not possible and we got offered free lockers in a location that is around 20 min walking from the apartment. Communication with the host works but we got answered always with some delay. Location is very convenient to explore the town.