Unfortunately, this guest and her partner have not stated the truth and were a bit of a nightmare. On their 2nd night we did have to send a polite message at 1.30am as there was very loud voices that could be heard by us elsewhere in the building and by neighbours. She was quite indignant and stated the next day they were "just talking" although we discovered after they vacated that they had actually MOVED the TV into the bedroom from the living room and it was obviously on very loud volume. They demanded to end the booking early the next morning via Airbnb support, to which we obliged with a refund of unused days.
She then stated that they wouldn't be home til late that evening but insisted on not paying extra for that day beyond the check-out time. We agreed to this also just so that they would leave. They had full access to all facilities in the flat for their paid stay. That evening, Fabiana even swore at my wife.
As for us not being open to requests, she requested when making the booking that 12 small bottles of sparkling water be waiting for them in the flat on arrival. Though unusual, we provided this as a courtesy. She also initially asked whether a friend with a dog could visit them, to which we declined as it is clearly stated in the rules that pets are not permitted and we explained we need to consider the potential for allergies.
We have been both guests and hosts on Airbnb and never experienced such rudeness from another user and we consider ourselves to have just been unlucky on this occasion.