We arrived late on Friday night but a housekeeper was waiting to let us into the flat. The airport is 20 minutes by car.
The flat is in a brilliant location with stunning views. Certainly worth climbing the 6 flight of stairs (easiest if you travel light). The flat is nicely furnished and great to use as a base to discover Lisbon. Tall travellers beware: the height in parts of the flat is restricted by the roof. I certainly recommend this flat.