I've been doing rinseless on the Audi and other cars in even the crappiest winters. ZERO issues. I use anywhere between 5-8 Eagle Edgeless 480gsm MF Towels in the dirtiest winters. Wring out and hange dry them and wash them in bulk every 3-4 weeks. I have 75-100 of them and just keep rotating them as I go.
The "power washer" I list isn't a power washer. It's just a powered garden sprayer that's output pressure is about that of a garden hose. I like it because I don't have to pump up a pressure sprayer and it does help knock-off any sand or snow.
I rarely if ever use a bucket / hose method to wash her. In summer I will use a hose t do the wheels and then pull her inside to do the rest. In winter I do hit the DIY rinse places to blast off the crud but not consistently. Mainly just because I don't like crud hanging off her