This is a hard review to write. I'll run the good, the bad, and the ugly in reverse order.
First the ugly. The bathroom vents a pretty bad sewer odor into the bathroom. It is the nature of this plumbing and it is what it is. My wife absolutely hated this. It was no big deal for me.
The bad: If you are tall, say over 5'10", you may find the bedroom level troublesome. My mantra going to that level was "no bonka da head". The clearance is just about 5' 10".
The bad: the lower apartment is very damp with algae growing on the kitchen wall.
The Good actually the Great. The location could not be better. The view is stunning. The bed is comfortable. Alex has done everything to make the apartment fully functional. Everything works as expected. Access to the Louis bridge couldn't be easier. Shopping, great shops, the Douro River are all very close by. Alex is extremely helpful with advice and suggestions.
You leave the dampness, low ceiling, and odor in the morning and only return in the evening. For me these were minor. For my wife, well that's another story.
I hope this helps...