Jean-Michel's place is perfect. It is close to public transport, parking (in a garage) is pretty easy, and the location itself if really central. We were welcomed by Ricardo, who was wonderful and full of advice on where to go and what to see.
The view is lovely, with a small deck off the kitchen and bedroom. The inside is modern, clean and has everything you may need for a short (or longer) stay.
The place is up several flights of steps (like many places in Porto) so pack light or be prepared to be a pack mule. I was lucky enough to babysit the car as Ricardo and my friend carried up my stuff - Thanks!