The flat is beautiful and in a prime location - a really short walk to the river and all the best spots in Porto.
The whole building is really beautiful, lift is a bonus if you’re travelling with heavy luggage. Flat is on the 4th floor with gorgeous views from the balcony, lovely on a sunny afternoon.
Sao Bento metro station is less than 5minutes walk but you won’t need to use it if you like walking - it was very handy though to take a train to the Porto beaches and to Douro (direct trains).
The flat is perfect for 2 people and suitable for 4 for a short stay I’d say.
A few notes - if you’re a light sleeper you’ll need ear plugs because the building is on a very busy street (with lots of construction work going on now). You’ll need to do some shopping on arrival as there’s no water, tea, coffee etc. Also toiletries and cleaning products are a bit sparse so depending on the length of your stay you might need a shower gel, dishwasher tablets etc. Plenty of shops nearby though.
All in all a lovely place to stay.