I stayed in the studio for a week during the Lisbon lockdown, so my impression of the noise levels won't be typical - there were no tourists, only locals, which made for a really lovely background hubbub when I had the window open.
The studio feels surprisingly spacious considering its size; it's very light as it's on the top floor. The kitchen is really well equipped, and when I asked for some extra items they were delivered the same day.
The building itself is quite noisy, very creaky stairs, and the downstairs neighbour was quite noisy; in normal times, however, I would expect that to be the least of the noise sources!
Check in is through codes and lockboxes, which they give you before arrival, so no worries there.
I enjoyed my stay at the studio and I would stay here again.