We were a group of 5 persons that perfectly fitted in the apartment. It is located in the middle of Porto and is close to literally everything.
Chris was very welcoming, and left a written paper about everything you might need: Wifi password, touristic tips, recommended restaurants and pubs around. That helped a lot ! PLUS he owns a pub next to the apartment, offer great food and drinks with a 20% discount ;)
The kitchen is well equipped with a coffee machine, some snacks were there aaaannd a bottle of Portuguese wine  !
On a another note, he was flexible with time: We arrived late on the first day and had to checkout late the last date.
Just to note that the two bathrooms are connected, separated by accordion door; and 2 out of 4 rooms have no windows. But it is was fine for us.