We never got to meet our host but a contact of the host came to let us in to the apartment. Comparing with my experience with airbnb this was not very special but it was sufficient.
The apartment is OK in a very vibrant area of Barca. Easy to access from the metro and easy to get about in town. However, it is a very residential area with lots of homeowners with dogs who get taken for a walk on the streets below - the smell is quite obvious. Apart from this, the area is OK.
As for the flat, it is functional. Not particularly homely or special but does the job.
I think it is a good value for money in Barcelona but dont expect too much.
It could be improved with some special touches but in general it is OK.