Imagine searching through Grandma's garage, and boxes of faded baseball cards suddenly appear in front of you. Doesn't your heart race a little? "Could these have any value?" I understand the buzz ...

The hit: Once a cashier activates the card for a unknowing buyer, the crook drains it fast—often before it’s even used Avoid it: Check the PIN/scratch area for tampering, grab from the back, pay with ...