Our stay with Sergio was perfect. Sergio was a great communicator before and during our trip. He was very knowledgable about the area and was ready for us with maps and recommendations. He even arranged a taxi for us at 4 am back to the airport.
The apartment itself is very clean and spacious. There were three of us staying there and there was ample space. It is located only two blocks from a street full of restaurants and shopping and 4-5 blocks from the beach and park. If you want to explore Barcelona more, it is only 2 blocks from the metro.
I would highly recommend this apartment.