Three of my friends and I stayed at Lucy's for 9 days and we really liked the cozy apartment: it was in a great neighbourhood with a grocery store and pharmacy down the block, steps away from the tapas strip on Blai, and close to the metro.
Lucy was very kind and gracious: our check-in greet and meet was thorough, she answered all my queries before and during my stay promptly (often within the hour), and looked out for us during our trip (she even offered to coordinate a cab for us to get us to the airport).
The apartment itself has sizeable, functional rooms, a well stocked kitchen, a clean, minimalist bathroom, and even a welcome bottle of cava!
Note the apartment is on the third floor and is only accessible by stairs, and one of the rooms faces the street with seemingly less sound insulation (the other two rooms were fine). The heating system (on-demand hot water tank with programmable thermostat) took a little getting used to, but it worked great once we got the hang of it.
Overall, this is a great place to stay if you are travelling with a group of people who are looking to be away from the tourist crowds and seeking a more local experience - you won't be disappointed!