We had a very enjoyable time in Barcelona during early December. At our arrival somebody was waiting for us so we could enter the apartment. The apartment is located just a five minute walk from the beach. Several restaurants, bars and supermarkets are also all in walking distance. Eating nearby is highly recommended, as prices explode as soon as you approach the inner city. Also there's a lot of variety here, e.g. the usual tapas, paella, Italian and Japanese cuisine, and a lot more.
Connection to public transport is excellent as well, a trip to the city center takes around 15 minutes by metro. So it’s a perfect starting point if you want to explore the entire city.
Because of the distance to La Rambla you have to expect some noise during the night from the local party folks. Depending on how sensitive are, this might pose a problem for you.
One thing we had a bit of a problem with was the heater of the apartment, which decided at some point to shut itself off. However we quickly received help on how to restart it. Hot showers working again!
We can recommend Lilia's place for short stays (we stayed for around a week which was fine). For extended periods we would probably choose something more spacious.