If you call someone a "whinger", you are critical of them because they complain about unimportant things all the time.
I think originally it meant 'to cry in a pathetic way' as babies sometimes do.
Now it is used to mean complain, usually about small things that annoy you.
You can whinge about the cold/the heat/the weather/the noise/high ceiling/low ceiling the cost of petrol/the cost of hotels and so on and if you do this all the time, one is often described as a constant whinger.
One of my friends describes her husband as a 'serial whinger' she loves her husband and says "I feel so sad for him, he can't help being as he is"
On occasions’ he pays her a compliment, and then takes it back. I quote;
"Darling you look lovely this evening: pity about the colour of your dress"
Naturally I would never suggest that our guest is any of the above.
Should this person stay with us again I have informed the staff to explain to other guest's to keep their voices low. [One of his complaints]
I have been in touch with my architect to draw up plans to raise the ceiling an extra six inches. [One of his complaints]
We can't find similar apartments in the area that are cheaper than Riverview Holiday Apartments, but we are scrolling through all AirBnB properties in the area to see if this is true. [One of his complaints]
Our guest seemed very clean when leaving, never the less we'll do our best to put more 'power in the shower' [One of his complaints]