Itching to catch a Ravens game without a season pass? Don't let the purple haze cloud your judgment while trying to score tickets, the Better Business Bureau warns. Person-to-person sales on online auction, classified and bulletin board sites are most vulnerable to scammers. Put your noggin to work before pumping your dough into the secondary ticket market, a $10 billion-a-year industry.

The Dos and Don'ts:

Do use legitimate, certified sites that include money-back guarantees.

Do buy from sellers with long, solid reputations.

Do scrutinize photos of tickets closely for any inaccuracies and alterations.

Do cross-check seat assignments with venue's Web site map before you buy.

Don't let sellers lure you away from the host Web page since the company may not guarantee off-site transactions.

Don't pay with a cashier's check or wire money.