The flat is a comfortable duplex, very clean, well-equipped (Dolce Gusto coffee machine, portable heatings, etc...), and matches the description and pictures.
It is very well located for sight seeing, shopping, eating, 600m away from Bolhao metro station.
The flat is handled by a company named The Porto Concierge, which is a very professional agency.
Our communication went pretty smoothly, as they explained you everything step by step once your booking is confirmed.
You get to pick up the key in one of their agencies (or you pay an 10eur fee to have someone to get you the key at your arrival).
I was welcomed at their agency 'Conde de Vizela Street' by Sara and Hugo, who are very lovely and speak a very good english if needed.
Everything went smooth thanks to their check-in app.
I can definitely recommand the agency and this place for a short or a long stay.