From the airport you have the Areo Bus ( http://www.golisbon.com/transport/airport-shuttle.html) or the metro (http://www.metrolisboa.pt/informacao/planear-a-viagem/diagrama/) direct to Restauradores square. If you choose this way to come, at Restauradores square you can take the Lavra funicular (http://guides.getportugal.com/lisbon/see/16424/06/lavra-funicular) , closes at 21h00, that takes you up to Câmara Pestana street, take right hand and 3 minutes walking you'll find Calçada de Santana. If you take a taxi, it will about 15 minutes driving to the apartment and it'll cost you about 15 Euros.