We attended an IT confernce in Barcelona for a week. We were 5 and everybody had his own separate room & washroom. The apartment is fantastic: It's very well equipped with a large living room / kitchen and surrounded by 5 private areas (bedroom / washroom). We were also able to do workshops in the living room as there was a white wall for projection and a quite solid Wifi connection.
The location couldn't be better - this is the heart of Barcelona - and the booking, check-in and check-out was very friendly, efficient and flexible.