We stayed 2 nights in Andre's place and it was a very pleasant experience. Andre was really nice and available to answer all our questions. When we arrived, we had two ''pasteis de nata" waiting for us :) The house was clean and had everything we needed. It's rather small and a bit dark, but comfortable (and I suppose you don't come to Lisbon to stay at home, at least during the day). It's also very well located, not in the center of historic Lisbon, but very close to one of it's bigger train and metro stations, so you can get there in 10 minutes.
Definitely recommend it.