I stayed at Didi's place with my best friend and it was just perfect. Each had their own room with privacy and the place really gives an old school Portuguese vibe (with a slight modern touch to the decoration!)
The place was better than we imagined and Didi was very helpful from the booking until the end. He gave us a few suggestions of what to do, restaurants, etc.
Bairro Alto is a great neighborhood for anyone who wants to be close to the action (bars, restaurants, etc.) Affordable and great! Definitely recommend.