I highly recommend Jacqueline's place. She is an impeccable host. Her apartment is conveniently located in a lovely part of Barcelona where you can still reach the more touristy parts quickly but also enjoy a more local scene. Her place is also extremely convenient if you are catching a Renfe train.
Jacqueline was so kind to meet us late when our flight was delayed and also was very flexible the following day. It was a pleasure to stay with her!