Marta is an amazing host. Every question we had before arriving, was answered very soon. She was so friendly to provide towels, bed linen,... (so we didn't have to take it onto the airplane). She also give us good advice about getting there, good places to eat with little children, where to rent a bike in the neighbourhood. Her sister was really friendly upon arrival and gave us al the information needed about the apartment.
The apartment itself is really nice and has every form of comfort needed with little children: baby cot, high chair, a place to change diapers and plenty of toys. Our children, aged 1,5yrs and 3,5yrs loved to stay at the apartment :-).
Barcelona is great and we were very happy to stay in poblenou. It's a small community in a big city: people are really nice (they know Marta ;D), it's a more quite neighbourhood near the sea, with a lot of shops, bars and restaurants. And only 10 minutes on the metro to get to the heart of the city. We even walked to Port Forum and Parc del ciutadella from the apartment.