I had a great stay at Mario's appartment. The room is nice and spacious (can be bit noisy sometimes because the bathroom next to it) with own doors to the balcony, which i loved. The communication with Mario, even while it was by phone, was great. He always is available for your questions. Next to it, he gives great advice about the highlights in Porto. After check-out (and when not possible to let luggage in the house because of there is a group coming which rent the whole house) Mario has an arrangement with the restaurant where the optional breakfast is served as well that you can store your luggage there till you really leave for 2,50 euro.