You can't go wrong staying IN THE MIDDLE of the Gothic Quarter of Barcelona (right off of La Rambla). Couple that with a great host, and you've found yourself a fabulous place to stay!
Pere walked us through a tourist map when we arrived since we were not completely sure what we wanted to do or what order we wanted to do our limited list in. His English was really good and he talked us through the different areas of Barcelona all while offering recommendations of what he thought of different areas, even going so far as to pinpoint some of his favorite places to eat with respect to where you're staying.
He also set aside space inside the fridge if you so chose to grab groceries or such to make your own food in the kitchen rather than going to a restaurant.
tl;dr Highly Recommend staying here if you're going to Barcelona!