We had a last-minute check-in at Cristiana's place and... that was a wonderful experience. Cristiana is a lovely and extremly helpful person. The last day of our trip we had a late night flight and she let us stay at her place longer without problems. My Mum got a flu and that was a real rescue for us (and thanks for a soup! :). Her place is breath-taking, with an amazing view on Porto and terrace that you can use during sunny days. The neighbourhood is calm and pretty, about 30 minutes walk from Clerigos Tower (you have also buses and metro not far away). The room for guests is big and well furnished as well as you have your private bathroom (!). To make the long story short - I totally recommend staying at Cristiana's!