insulated garage (and garage door) with gas heater hooked into house gas line FTW!!!
i'm also in WI, but just heat up my garage when needed to do washes/details. if i didn't have the warm garage, i would stick to using the self-wash bays and merely spray the majority of the salt/dirt off the car in the winter. definitely make sure you rinse under the car every week or so during the road salt season.
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