The secondhand luxury goods market has exploded. Just look at the rise of stores like The RealReal or Fashionphile. But how can you tell you’re buying a real, genuine Chanel bag or Hermès scarf? Some online resellers say authentication is the answer. To find out how it works, we went to “Into Archives,” a luxury reseller in Manhattan to see what professional authenticator Graham Wetzbarger looks for when examining the goods. For more, listen to the Planet Money episode “Seven allegedly fake Chanel bags vs The RealReal” or click the link in our bio.