I totally feel your pain, and your '2 min' title is genuinely about spot on for us darker colours.
My customers expect to see my van looking tip-top for each job, meaning i'm currently spending around 8hrs a week cleaning mine. I only did mine yesterday after another long distance trip over to a job in the depths of Norfolk, and it's now raining which means although it's saying dry tomorrow, I know the rain today will leave the roads damp for my early start to the depths of Kent, meaning by the time I get to my job, it will be filthy again.
I love Black in the Summer, but loathe it in the winter
However, moving from similar wheels to you, over to my current banded 19s has saved me several hours a week in wheel detailing
We offer 2 services. We either apply a semi permanent protection to new Caravans and Motorhomes, or the main part of my business restores common fading issues that effect most manufacturers from around 2 years old, normally starting with a dull front panel. So depending on what you have, dictates what you will need.
We cover the whole UK.
I'm at ME14 tomorrow, Southampton last week etc etc.