What ??? ... If your broker came at with a 30% increase, assuming you have a good loss ratio, him (or her as the case may be) would be kicking their lunch pail down the road.
Assuming Armageddon is off the table for the prior year, any broker that comes at you with a 30% increase has not been doing their job. The keys to manageable insurance cost are pretty simple;
First, search out the best broker that you can find and that understands your business. If they promise you the world after a 2 hour meeting, you don't want them. They need to be with you for 30 to 40 hours before you commit. The guy that insures your house, pickup truck, boat, and quad, is not the guy you want insuring your trucks. I guarantee he/she doesn't know sh*t about trucking insurance.
Second, with your broker you examine every insurance payment and claim going back as far as you possibly can. The key is to determine your loss ratio over 3 years, 5 years, 10 years, and 25 years. (This part will sicken you ... from this number you will know what you paid insurance companies, and what they paid you.) Somewhere in this exercise you want to be able to say I have/had a 5% loss ratio. When you can do that, you have leverage. The lower the ratio over the longer term increases leverage.
Third, you, with broker in tow, want to sit down face-to-face with your insurer ... yes, that's right, the actual insurance company ... they folks that write the cheques. You want them to become like family. You want them to know your business as well as you do.
Lastly, you're in this for the long haul. You want to establish a long term relationship with your insurance company ... the longer, the better. You'll even want to consider paying a bit of a premium in the beginning to be able to stay with one company. In crunch time it pays off huge.
If you're one of those companies that bounces around every year, you're just a window shopper, and insurance companies will treat you like one. They won't care if you like what they are offering. They don't care if you change. They do know that you'll be back in about 5 years ... if you're still in business.