I can rinse my car off in the indoor heated garage where I park under my apt building.
I will rinse a new car off pretty often. Say the first four years... I rinse, then run a Waterblade over it fast.
After that, depending, i just let it stay dirty.
Though my latest car, being a bright yellow, I probably will rinse it off more often than my last car for the last seven years i owned it (out of 13 years) . Which was washed about once a year, and that only a rinse off.
My last car... usually it would be after raining, and when I pulled in I would wipe it down with a paper towel. Mainly the hood, and doors..
Ratty.. but honest.