(MONEY Magazine) – Most credit experts say that two or three cards is sufficient. Scott Bilker has 80 of 'em. He's charged automobiles (long considered a credit-card no-no) and once took out $62,000 in cash advances on four cards at 0%, invested it all in a money-market account paying almost 3% and turned a $1,800 profit in 12 months. "It was fun," Bilker says.

Another poor sucker recklessly wallowing in red ink? Hardly. Bilker (yes, that's his real name) has a FICO credit score of 794 (out of 850). As founder of Debtsmart.com and author of Talk Your Way Out of Credit Card Debt, he scoffs at such traditional debt-management wisdom as "cut up all of your credit cards." The problem doesn't lie with carrying a balance, he argues, but with astronomical interest rates and late payments. "Being late," he warns, "is the greatest sin." To keep his rates low, Bilker is regularly on the phone seeking better deals from banks. Of course, this is what the guy does for a living. But with some negotiating savvy, you too can lower your rates. Here's what you need to know.

-- Banks are at your mercy. "We're paying them," Bilker notes, in the form of fees and interest. It costs banks plenty to obtain customers, so it's usually in their interest to keep the good ones. That can give you some leverage when requesting lower rates: If the bank refuses to negotiate, threaten to take your business elsewhere.

-- You need plenty of credit options to wrangle the best deals. Bilker uses this strategy with his 80 cards (nine of them currently carry balances): For two weeks he and his wife each use just one card. Then they both switch to a new card. When the has-been bank sees no activity on the card, it often rolls out extra-sweet offers, like 0% no-fee balance transfers.

-- Always bargain for better. Discover recently slashed Bilker's rate from 7% to 4%, but only after he first turned down 6% and 5%. He says the Discover rep actually told him why they could afford to cut him a deal: "Banks know enough people will be lazy and forget to pay on time."

-- Never overspend. Snaring a great credit deal comes second to what you're actually buying, he says. "If I bought a $62,000 Lincoln Navigator, even at 0% for one year, I'd still owe about $58,000 at the end of that year." Ask yourself: Can I really afford this purchase?

As interest rates rise, will good credit deals go away? Bilker thinks not. "Competition between banks is too fierce," he figures, "and those customers are too precious." --MEGAN JOHNSTON