Consumer alert: Beware of the forced car rental "upgrade"

They're desperate to make an extra buck. How low will they go?

The forced car rental upgrade is one of the oldest travel scams in the book.

Here's how it works: You show up at the rental location, and an agent informs you that unfortunately, they're out of cars in your vehicle class. But for just $20 a day extra, you can "upgrade" into a bigger car — which happens to be available now.