We LOVED staying in Sara's flat in Principe Real. We were within walking distance of many things we wanted to do, a local market and great restaurants yet the area was quiet enough for us to have some peace and quiet (and sleep :)).

The apartment was beautiful with high arched and vaulted ceilings, wooden shutter window treatments and polished wood floors. After staying in a somewhat tight guest house it was a luxury for the three of us to spread out again. It was great to relax in the living room with some wine after a day of touring. The apartment was clean, clean, clean and had every countless amenities (espresso maker- check, a stocked bookshelf and cookbooks to peruse-check. Sara even welcomed us with a bottle of Portuguese red!). The beds were comfy and she even had a washing machine of which we were in desperate need. The apartment is on the third floor which could be an issue for someone with mobility issues but posed no inconvenience to us at all.
Sara was a gracious and helpful host who lives in the same building. She was flexible and checked my son it separately from us so we could start our touring day (he arrived later). She even came down to give us some basic washing machine instructions :). Highly highly recommended. I am already planning a trip back with my husband and will plan on staying here again. After touring through most of Lisbon I think the Principe Real area really feels more like visiting "home" and is away from all the crazy hustle and bustle. Sara will also give you some tips and information about staying in the neighborhood which I found helpful. Stay here !