I sweat profusely, so I ride in cycling attire and work in work attire. We have lockers, but not showers. A birdbath in the sink works well enough.

I wore out the crotch of enough jeans back in the 70s that I wouldn't ride in anything I expect to keep looking decent anyway. My commuting shorts are the cheapest I can find without a diaper-like chamois. Thin works best for me. Last ones I bought were four years ago at either $25 or $30 each. I own six pairs of them. They'll get me through the winter under my bib tights, but I think they'll need replacement in the spring.

On Mondays I load the panniers with work clothes and food for the week. Tuesdays and Wednesdays I can ride any bike I want. Thursdays I bring the panniers back home loaded with laundry.