Catarina & Alexandra are indeed perfect hosts, right after our arrival they shared their immense knowledge about the city with us! Their recommendations made it easy for us to enjoy the city, even though we had so little time.
The Flat is as described, nicely furnished, with plants, wooden floor, even brighter than I expected - and perfectly clean.
The Flat is located in the very center of Porto in the old town with the main sights in walking distance. (You are able to reach the Airport shuttle by foot, which is very practical if you have to take a flight in the early morning)
We would always return, but only for a longer stay.