Go to a good detailing forum like Autogeek and do a search for Optimum No Rinse or ONR. Here's a link to the product below. There's a very simple two bucket method that allows you to wash in garage in comfort. I"ve used it on dark cars and noticed no damage to the surface.
http://www.autogeek.net/optimum-no-rinse.html
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2022 M3 xDrive, Brooklyn Grey over Tartufo
2021 Tesla Model Y
2019 MB AMG C43 (Sold)
2016 M235i xdrive, Alpine White, Terra Leather, Orbit Gray Wheels (Sold)