Cristina's Apartment is situated just in the very very centre of the oldtown. It's very easy to find, nevertheless if you'd encounter problems, Cristina will help you out. She's a warm person and I immediately felt at home in her flat. It is a good mix between space for your own stuff + authentic charme because Cristina also leaves some of her own stuff there - which I find very good. During the weekends nights can get loud, but that's just what happens when you're in the middle of a city. Just put in some earplugs or go party yourself :).
If you're looking for an authentic place to stay in the middle of the city: book this apartement.
Ps: the apartment really looks as nice as on the pictures!