Mad Catter: Mike and Frank dive headfirst into America's junk yards and barns in search of rare collectibles. They begin in a treasure-packed machine shop. (S4, ep 13)

Not So Cheap Thrills: Mike and Frank go deep into rural Minnesota to check out collectors with rare antique signs and vintage Knotty Peek peep show machines. (S4, ep 12)

Big Boom: Rick's staff dice with death as they restore a 1900s signal cannon. They also fix up a 1950s Italian folding bicycle and, later, hold their first shop auction. (S4, ep 9)

Down & Dirty: The team are in for a rocky restoration when a three-wheeled 1972 Honda ATC rolls in. Meanwhile Ron and Tyler begin to make big plans for Rick's bachelor bash. (S4, ep 7)

Feel The Heat: Rick has a puzzle on his hands when an unidentifiable antique cart rumbles into the shop. Can he solve the mystery of its maker and get it back on the road? (S4, ep 6)

Dirt Bike Duel: Rick finds he can't say no when NASCAR driver Greg Biffle asks him to restore his 1970s Montesa motorcycle. But has he taken on one challenge too many? (S4, ep 5)

Train Trouble: The shop gets to work overhauling a NYC police call box. Tyler tows in a 1947 railroad speeder. But has he underestimated how much it will cost to fix? (S4, ep 4)

Sticky Fingers: Rick and his crew race against the clock to restore a 1950s taximeter. Plus, Brettly gets his big break when he oversees work on a 1800s gum vending machine. (S4, ep 3)

Harrison's Vendorlator: Rick Harrison stops with a one-of-a kind Pepsi dispenser. Plus, the workshop feels the pressure when it is hired to restore a very important sign. (S4, ep 21)

Call The Count: Rick rises to the tough challenge of restoring a classic guitar in time for Brettly's birthday. A rare Pak Trak hunting scooter also arrives at the shop. (S4, ep 20)