When I was working at a dealership we had to stand outside for most of the 8 hour day...and change buckets as and when they froze over!
The only plus side was that it got dark earlier so we finished early, but my hands were so cold it was untrue. Thinking about it, I hated that job!!
Washing cars (outside) in winter is no fun.
I did the same job many years ago, I used to have to run the pressure washer with the tap switched off for a couple of secs every evening so the water didnt freeze and expand, busting the pump. Even a wrung out sponge would be a solid lump in the morning!
I got talght the 'proper' way to thoughrally wring out a shammy by my collegue, an ex convict, something he learned inside so that you didnt get your feet wet.
The air running up the vacume hose was so cold it'd make the metal pipe feel white hot in my hand, wahing hands afterwards was a 'mare (if you've ever ran your hand under a hot tap that is so hot it actually feels cold and messes with your sense of temperature).
My tip to valeters (or window cleaners) is to use cold water to wash the car, you wont feel the wind chill so bad after a while where as if you have hot hands as they are drying off you will.