Commercial truck insurance? Just started my own trucking business

I just started my own small trucking business and I need to get commercial truck insurance. I'm not sure what coverage I actually need or which company to go with. I've heard that commercial insurance is way more expensive than personal car insurance.

I'm trying to figure out the minimum coverage I need to be legal and then what extra coverage would be smart to have. Has anyone here own a trucking business? What insurance company did you go with and how much are you paying? I want to make sure I'm not overpaying but I also need to be properly covered.