Combine your Home and Auto insurance.
This isn't much of a tip, everyone knows to do this, right? Well it took me long enough to get around to it. I finally moved our home over to our Auto insurer earlier this year. I had looked into it a few years ago but we weren't eligible. We had had a homeowners claim a few years ago, you have to be claim-free for 3 years to get home insurance, at least with our Auto company.
Anyway we finally moved it and we are now saving 15% on our Auto, the homeowners was the same price at either insurer.
With 7 cars and a bunch of teen drives, the 15% is really a nice chunk of money.
So go do the Discount Double Check at State Farm (that's who we use) or other insurance companies that give you a discount for combining Home and Auto.