Not very often. Third wash since Sep.
I have the luxury of only going out when I want to so normally it just needs a going round in the garage with the waterless wash and wax.
However, I've been building a bespoke cupboard for the daughter and the only way to cut Contiboard, to get a perfect edge, is with a router. A hand or rotary/jig saw causes chips, no matter how careful you are. Unfortunately, even though I did it in the garden on a couple of workmates, well away, some of the sawdust drifted into the garage.
Using a router and giving the Conti 3 increasing depth passes causes lots of sawdust. I decided that it needed a rinse.
Nice day so a full mini detail.