I moved to Utah when I was 23. When I went to register my Chevy Nova, I was told I'd have to pay property tax. I'm renting, I said. I don't own any property. On your car, they said. Plus a registration fee, of course.
When you register a motor home in Utah, you pay a property tax based on value and a registration fee that includes an additional amount based on weight. I didn't know that last part. So when I went to the DMV in 2010 to register our new-to-us rig and the clerk asked me what the motor home weighed, I said I didn't know --- because I didn't, off the top of my head. The clerk asked the me for the name of the manufacturer and told me our motor home weighed 18,000 pounds. She didn't tell me the fee had anything to do with the weight, but I should have surmised. Actually, our rig weighs about 11,000 pounds and can't safely weigh more than 14,000 pounds when fully loaded, which it never is. But for three years we paid more than we should have when renewing our registration, until somehow it sunk into my brain that the fee is weight-based. Duh.
This year I took our owner's manual to the DMV as proof of weight and stood (sat actually, because it's a "take-a-number" system") with 75 other people until I was called up. It all was pretty quick, considering how many folks were waiting. And our annual fee is now about $65 less.