I visited Lisbon for 4 days and stayed at Rita & Helder's place.
Before arriving, me and my girlfriend were a bit weary since this place was not our first choice, but ended up being one of the few available at the time of booking. But after entering the apartment we were positively surprised. I don't know exactly what it is, either the lightning or maybe the angle of the photos on the page, it doesn't do it justice, or at least that was the impression we got. In actuality the apartment is extremely cozy, has great light, and a nice busy view to this street locate near the historic center.
Everything was extremely clean, and the communication was fast and without any problem whatsoever. The location is nothing short of amazing, you can walk everywhere from there, and even if you want to go nearby regions such as Sintra or Cascais, you have public transportation less than 5 minutes from walking the front door.
I can only point two negatives: first, the house is located near a ton of restaurants, so prepare to dodge a dozen of greeters inviting you to their establishment once you step out of the front door. Second, at night, if there's someone residing in the floor above you can faintly hear footsteps and other noises - this is nothing that we would not describe as loud, but something to note in case you are susceptible to those types of noise.
Overall, great experience and next visit we are definitely thinking about staying with this host again!