We had a very nice stay here. The apartment manager took care of everything and even picked us up when we arrived and drove us to the location. Good communication and everything was fine.
The only thing to remark, and unfortunately this does not apply directly to the landlords, but the downstairs neighbour has a dog and when the dog is left alone it barks non-stop. Inside or outside, it doesn't really make a difference because Portuguese buildings aren't well insulated. The lady was friendly and tried to come up with solutions, but there wasn't really anything to do about it. It made it so we could rarely sleep in and during the day we weren't able to work from home because of the non-stop barking. When the dog wasn't alone we never heard her, but when the owners were gone... . So if you're a light sleeper or someone who doesn't like to be disturbed during the day - it's worth considering.