The strong point of the Sagrada Familia apartment is the very good location. From the living room you have the nice Sagrada Familia view and it very close by at a metro station to get easy the other attractions of the city. It also very close by at a supermarket.
The living room and the kitchen are very spacious, but for an apartment that should be for six people, it might needs more dishes/flatware.
Regarding the bedrooms, one of the double room should be better as a single room (it is very small for two).
The apartment in general was clean, but maybe the atmosphere is a little bit cold.
We were in 5 and we arrived in Barcelona with a mini van, that we would like to park in a private parking, possible near the apartment. Sergio helped us to find a good solution very close by the apartment.
The communication with the host was very clear and detail.
Andrea (an italian guy who lives in Barcelona from a long time) welcomed us and introduced very well the place and the city, recommending where to go and what to visit.