Can You Afford a Sexual Affair?

July 10, 2008— -- What's the price of infidelity?

How about $300,000? That's how much Christie Brinkley's soon-to-be-ex-husband, Peter Cook, allegedly spent to keep his 18-year-old mistress quiet. Feeling a little more frugal? Try $4,300 -- the price tag for former New York Gov. Eliott Spitzer's alleged night with a prostitute.

While Cook and Spitzer may represent extremes, they're not alone in opening their wallets to satisfy their extramarital appetites. Experts say that infidelity frequently manifests itself in sly spending on new wardrobes, dating Web sites and more.

"I really don't think a lot of people think of the financial aspect of it, but it's a huge part of it. I don't think you can cheat without it also being a financial betrayal," said Debbie Then, a psychologist and the author of "Women Who Stay With Men Who Stray: What Every Women Needs to Know About Men and Infidelity."

Ruth Houston, the author of "Is He Cheating on You? 829 Telltale Signs," estimates that between 70 percent to 95 percent of people who cheat on their spouses see their trysts affecting their bank accounts. That includes everyone from rich businessmen to people on welfare, Houston said.

"If a person is involved in an affair, there's money being paid somewhere along the line: to hide it, to initiate it, to maintain it," said Houston, who was once married to a cheater. "It happens at all economic levels."

Noel Biderman, the president of a Web site dedicated to infidelity, said some members of his site have reported that their affairs cost as much as $10,000 a year thanks to mundane expenses such as cell phone calls and cab fare as well as more luxurious spending, such as hotel stays and fancy gifts.

One man, Biderman said, spent upward of $40,000 a year to have flings with women across the country.

"If it was the right woman, he didn't care if she was from Missouri or Miami," Biderman said. "He was prepared to bring them in or go see them."

Spending on an affair has become easier to do since the advent of dating sites, Then said.

"You can sit in your office and do it. I think just putting it at somebody's fingertips makes it easier to do and easier to spend the money on," she said. "It's not like I'm out walking in a bad neighborhood looking at a strip joint."