Natali is an amazing hostess. She is very responsive and very nice. I travelled with my husband, mom and our baby and she arranged for us a nice crib for our little one. The apartment was very clean and seems to be recently renovated. All of us were very happy with the shower, which was very powerful, and our beds, and all the appliances were very good.
The location of the apartment can be a bit of a hassle when you have a baby, due to the distance from the city center and to the uphill. On the other hand, you can have a nice view from Barcelona when walking around the neighbourhood. There is not much to do on the vicinity, but you can definitely find supermarkets and very few restaurants/bar. The apartment can be very humid, because there is not much ventilation and sun light (it is an underground apartment). But is has air conditioner that works properly.
If I would go back to Barcelona I'd prefer to stay closer to the tourist attractions and in an apartment more accessible, because of my family. But we had a good time, and most of the cons we already knew before getting there. It is a very nice apartment if you plan to spend most of the day outside.