Grocery shop - either a small Coviran or Carrefour on La Rambla.
We were there with 2 small kids (5,2) and the size of the apartment was perfect. 2 bedrooms are very much needed if you want to sleep :-) The building and apartment are new, so we must watch our kids carefully. The day before our last day has been opened a pool on the roof, which provide a great experience between hot lunch and afternoon siesta.
The washing machine was missing, but you get used to it. The value for the money of this apartment was very worthy.