If you want some privacy in your carport and a bit more shelter for your car—but you don't have the time or money to convert it to a garage—consider adding privacy partitions or shade lattices to your carport rather than building walls.
Try installing a lattice screen or a vertical slatted fence made out of wood or a low-maintenance, weather-resistant composite material like TREX. As long as the new "wall" isn't solid or doesn't completely reach from side to side or from top to bottom, the carport won't be considered enclosed or "livable," so it's not subject to so many rules. Leave one side of the carport completely open so you can drive in and out.
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