Communication was excellent. I had one or two problems and the responses were very helpful, and very fast. I appreciated that the flat was equipped with all the household things you need, like coffee, oil, salt and washing detergent. Location is really perfect - check out Augusto next door for brunch.
On the down side, there was a lot of noise from the visitors upstairs - you can hear every step on the wooden floorboards very loudly, and unfortunately for the first week of my stay there were a bunch of tourists upstairs partying until 4am every night. Once normal people moved in it was fine.
Also note that the stairs are very narrow and very steep, even by Lisbon standards.