First of all, I should mention that the location is on Pink St., the party capital of Lisbon. The address shows an address around the corner. This is where tourists come to get drunk. It is loud. Between around 6AM and noon it is pretty quiet. There are street performers, sometimes playing the same music every day. A couple of nights in a row, an almost-all trombone band (I think there was one sousaphone) played from about midnight to 3AM. There are chanting British people, even when it isn't football season. The front of the entrance is outdoor seating for a bar, so, late at night, after pressing through the crowd, a bouncer will undo the rope to let you in, and then you will have to shoo intoxicated people from your doorstep to get inside.
The windows and wooden shutters actually do a decent job of dampening the noise. With the addition of wax earplugs, it was a low murmur most of the time (sousaphones and chanting Brits excluded), and I was able to sleep.
It may seem like I am giving this place a bad review, but I am not. It is what it is (you should just know what it is) and if you like to be where the action is, this place is for you. Cais do Sodre, the central subway/train station, is a couple of blocks away. The apartment is lovely and clean. There is air conditioning, a washer/dryer combo, and an induction stove. The building has an elevator. There is a lot of good food and drink nearby. Sol e Pesca, a famous canned fish restaurant, is directly across the street. I also recommend Palácio do Kebab, where you can get a giant plate of delicious meat and a drink for 5 Euros. Somehow, the quietest place nearby is called Bacchanal, a little wine bar that looks like it used to be a pharmacy and has an extensive selection of wine and spirits.
All things considered, I would stay here again, but probably not for two months.