When I first began, I was primarily only doing fleets and heavy equipment. Found a broker that classified me as a mobile detailer. Think I was spending $500 a year for 1 million / 2 million liability.
Now that our work focuses on large scale commercial flatwork, and our limits now include 5 million liability, umbrella liability, 1 million vehicle commercial and workman's comp, with over $10,000 per year.