I had a fantastic stay at Ricardo's apartment. The apartment appears to have been renovated relatively recently, but it is in an old building and they have maintained a lot of the original touches (i.e. woodwork, doors, windows, blue tiles etc). It is beautifully decorated and has such a charming and clean aesthetic. The location is also great as it is in the middle of the Baixa neighborhood, which is in the center of everything (between the Castelo, Praça do Comercio, and Bairro Alto). The hosts were also easy to communicate with and were very friendly. I would highly recommend staying here while you're in Lisbon!