I stayed at Sergio's just for one night with 7 other friends.
The apartment is exactly how it looks in the pictures: it is roomy, clean and very well furnished. It faces gran via and it is very close to Plaça Tetuan; a great zone of the city.
Sergio has been professional and at the same time friendly, he gave us clear and precise instructions for everything and always answered for every request.
I highly recommend Sergio as a host and his apartment.