We really enjoyed our time in Lisbon. One of the reasons is Andrés Flat. It is really nice, with a lot of details to discover: From Star Wars and Super Mario to old Cashboxes and typewriters all over the place.
André is a very friendly open-minded guy with useful suggestions about the city. The location is good because by metro you can get everywhere you want very quick.
We really recommend this place.
P.S.: We read in one comment that there is no window in the Star Wars room. But there is one. So no worries.