Sandra's place is located in a great area of Lisbon! We arrived quite late on the first night, so we had Carlos arrange a transfer from the airport and he kept in touch throughout as we were stuck in immigration for nearly an hour. Maria, who welcomed us, is a charming Portuguese lady who let us into the apartment and showed us around.
The WiFi is fast and the TV was a nice home comfort when relaxing after a days walking (or rather hiking) the hilly, narrow streets of Lisbon. The bed was comfortable and the sheets clean. Our only gripe, which is not with the host, and comes as part of the "charm" of such old buildings is that the ventilation in the bathroom is poor, which led to things like towels and clothes remaining damp.
Overall, highly recommended, and with hosts that go the extra mile its a win win!