I stayed one night at Carlos' apartment and enjoyed it. The place is very clean, bright and very nicely modern furnished, better than in the pictures!
The location is great, the tube station is few minutes walk away and I reached the city center in less than 15 minutes.
It is also very close the airport, litterally 5 minutes away by cab (it cost me 8.5€), so very convenient for me that had early flight back in the morning.
Carlos is very nice person, he was flexible whit my check-in and communication with him was great at all stages.
I would recommend staying Carlos' apartment and I will book again next time I am back in Lisbon!