Myself and my girlfriend stayed at Andrea's apartment, and we absolutely loved it! Prior to our arrival Andrea was very helpful, providing loads of information on how to get to the flat.
When we arrived Andrea's wife was there to meet us and show us around. She was very friendly and made us feel at ease. The flat itself was beautiful and immaculately clean! A perfect size for a couple, and in a great location just a stones throw from Sagrada Familia! It was a bit of a walk to other places like the beach or Gothic Quarter (about 45 - 60 mins) which meant we did get some taxis to and from the flat. But there is public transport available too nearby :)
I would definitely recommend Andrea's place, it was out little home from home on our trip! We would definitely ask to stay again should we come back to Barcelona!