We stayed at Luis and Madalena's place for several days, and we loved it! Close enough to the core of the city that it's not an inconvenience to walk, and far enough away that it's calm and neighbourhoody. Upon our arrival, Luis and Madalena took the time to go through the apartment with us, and explain their tips and tricks to enjoying the city, including which places to eat, how much we should expect tickets to cost for different attractions, walking routes, etc. Our trip went a lot more smoothly thanks to this! They also welcomed us with a bottle of Port and Portuguese pastries - yum!
The space itself was lovely and quaint, with everything you need. Additional heaters if you get cold, towel heating rack, washing machine, blow dryer and they also picked up some coffee pods for us! Unfortunately, during out stay there was construction next door, so some mornings were a bit more noisy than others, but that was to no fault of the hosts.
Overall, we enjoyed out stay here, and would definitely recommend Luis and Madalena's place for your stay in Porto!