Cristina's appartment is really well located. Its very close to the beach and very close to the metro stop (about 200m, L4 Poblenou). The metro can bring you right into the city center. We were very happy to stay at her place. Eventhough we arrived late at night, she was welcoming us with two bottles of water and everything was ready! The bed is quite comfortable as well and the room is spacious enough for two persons.
There is a bar nearby the house which can cause some minor noise at night. We werent really bothered by it, but we did use earplugs.