We have stayed (4 adults) in the apartment for 3 nights in June. Communication, location and our check-in/check-out were great and without any problem.
I'm also (super)host on Airbnb in Slovakia thus I think that few bad ratings from last month are not eligible. There are small details to improve - e.g. cleaner drain in the shower. Apartment looks little better at the photos than in real. Maybe small renovation can help but beds were comfortable.
I finally recommend this apartment as a great option to explore Lisbon!