Amazing!
Diana's place is peaceful, clean and beautiful. I was greeted very well! Great host! Great location: less than 10mins walk from La Sagrada Familia and 2mins walk from beautiful Hospital de Sant Pau (you can go inside for €13, it's very beautiful). Very near her place is a bus station from where you can easily go wherever you want. A very important thing for me was the night bus, because I was travelling alone and it happened to me to stay out a little bit late. Night bus line N4 (you can catch this bus at Placa Catalunya, just like every other bus) will take you to the bus station which is RIGHT IN FRONT of Diana's place.
There were also some other guests in room next to mine, but since there are two bathrooms (one main and one that is just a toilet) in apartment, I never had to wait for somebody to finish so I could go inside, which was really nice.
I would definitely recommend this host and this place!!!