We got into Lisbon in the early afternoon and arrived at the flat by mid-afternoon. We were met by a woman who gave us one key to the flat.
We slept that night in the only bedroom with air conditioning (it was hot in Lisbon in July). The A/C must have had a problem with the compressor, because every 10 minutes it made a very loud buzzing noise like an alarm clock. My partner moved to the other room without A/C and sweated through the night.
Next morning we woke up to loud construction sounds, which happened every day.
By the end of the second day, a very bad sewage smell began emanating from both bathrooms, but particularly the master bathroom. We ended up closing that bathroom door and never using it again.
They were responsive when we reported the sewage smell. Their fix was putting a very intensely scented chemical in the toilet, which only masked the scent of sewage and was absolutely unbearable. When we mentioned the scent was unacceptable, the owners said "that's the smell of Lisbon in the summer."
Most unsafe was the light at the top of the stairs was out. There is no interior light in the stairwell once you close the apartment door, so it is extremely dark. We had to be very careful not to fall down the stairs. They "fixed" it on day 3, but by day 4 it was out again. We left on day 5. But paid for 8 days. Very unsatisfied with our stay.