David's place is great! It is close to a bunch of cure portuguese restaurants where you can try all the local delicacies (bacalhau!); and has a great view. His home is in a location where you can walk to the local bars around as well, and all in all a great deal for the money.
David and his family are really nice, and run a little coffee shop nearby. Would definitely recommend to anyone visiting the charming city of Lisbon.