I stayed 2 weeks in the studio of Ana & Vitor and I had a really good time. I had to work during daytime (at home), the neighbourhood is quiet, there is a bakery/coffeeshop and a mini supermarket within 20 meters, which was perfect for me. It's a 10 minutes walk to either Bairro alto or Rossio.
Ana welcomed me and gave me interesting information about Lisboa, and during my visit she contacted me about cleaning the apartment etc. All worked out really well! I woud love to come back one day..