We had four nights at Sarah & Pedro's appartment in May. The living room and kitchen are a good size and it is ideally located for exploring the old part of Lisbon. We were picked up by Maria who works at the cafe downstairs from the appartment and we ate there on our first night. It's worth a visit for any music fans as they have an impressive collection of B&W photos of bands and singers from the 1980s. Sarah recommended a vegetarian restaurant next door to Maria's father's place and it is also worth going to.
Pedro was around to help with any problems or questions we had and if you are new to Lisbon it is a good idea to pay the 40 euros for the transfer from the airport. The Metro trains run regularly but the ticket system is a bit confusing and if you have had an early start to your day like we did, you will just want to get to where you're staying.
One thing to emphasize is quite how steep the third staircase is up to the appartment. The steps are also quite narrow so if you have any issues with going up and down stairs this probably isn't the best place for you to stay. We were grateful to Maria and Pedro for helping with our luggage when we arrived and left.