It is a challenging climb to the 5th floor as there is no elevator in the building. Be very careful when carrying your luggage as the stairs are uneven between the 3rd and 5th.
Unfortunately I couldn’t use the very large upstairs bedroom (under the roof) for most of my stay (2.5 months) as it got really hot from mid June and there is no air conditioning in the apartment but only an electric fans available.
The apartment is very central and only a 15-minute walk from Chiado. The street can be noisy at night because of the tram (running till 1) and customers from the speakeasy bar downstairs that stays open until 2AM (despite covid restrictions).