Even celebrities who are past their prime make a ton of money.
Speaking engagements, private performances or simple appearances can bring in hundreds of thousands of dollars.
Celebrity Talent International is an agency that represents huge stars like Adele, Elton John and Angelina Jolie, booking appearances for these stars and hundreds more.
Many of the appearance fees are listed on CTI's website and are shockingly high.
Decades after 90210 made her famous, Shannen Dougherty is still making a ton of money. Same for former musician/reality stars like Clay Aiken and Bret Michaels.
And you won't believe what the former Mr. Britney Spears makes.
Shannen Doherty makes more than $100,000 per appearance.
Dougherty's peak was about 20 years ago when she starred as mean girl Brenda on "Beverly Hills 90210." She's had a few gigs since, but nothing notable in the past couple years.
Roseanne Barr still rakes in $100,000 per appearance.
Roseanne is famous for her sitcom that ran from 1988 through 1997. Since then, her career has dried up. Her Lifetime reality show "Roseanne's Nuts" was cancelled after one season.
Clay Aiken charges between $100,000 and $150,000 per speaking gig.
Aiken was the runner-up on "American Idol" in 2003. Since then, he's had a few songs on the radio. But he still has a lucrative speaking career.
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