Francesco really is a super host, very kind, helpful and friendly. I thoroughly enjoyed my two-month stay at his flat in El Poble Sec. The flat is ideal for two people, although with the sofa bed it can accommodate more.
The space is very well organised and extremely well-equipped: I stayed as a solo traveller for most of the time but when my daughter joined me, we found everything we needed to cook full meals!
Both the bed and the sofa bed are very comfortable and there is plenty of storage space. Franceso lives nearby, so if there are any problems (there weren't any) he is on hand and is very quick to respond.
As for the barrí: El Poble Sec is a lively neighbourhood, very much a local area and not touristy, which is great in giving you a sense of 'real' life in Barcelona. It is extremely easy and inexpensive to get around the city using the metro or buses, but it's equally easy to walk everywhere in a short time.
My personal recommendations for the daily life in the neighbourhood: enjoy the cafés and restaurants on Carrer del Parlement (where traffic restrictions mean the pavement cafés are quieter) ; buy your fresh food from the lovely Mercado de Sant Antoní and your artesan bread from Pa Serrá on Carrer D'Olivera, have lovely walks around Montjuïc, and generally make yourselves at home. I highly recommend!