I currently have business Insurance policy that will cover snow plowing. I have my auto policy through another agency. My business agent is telling me I don't need commercial auto as this will be double coverage. My business policy will cover my plow, spreader and damage I may cause to vehilces or buldings while driving or plowing, and a number of other things. Most of you guys seem to have both policys. Why would you need commercial auto if you have commercial business?