What must be done before processing a supply purchase transaction at Costco?

Before processing a supply purchase transaction at Costco, it is essential to scan the supply membership card. This process is crucial because it verifies that the individual making the purchase is a member, which is a requirement for all customers at Costco. Membership ensures that only authorized individuals have access to Costco's wholesale prices and exclusive products, thereby maintaining the integrity of the membership model that Costco operates on.

Scanning the membership card also facilitates the transaction process by linking the purchase to the member's account, enabling accurate tracking of purchases, inventory management, and providing members access to their purchase history if they require it. This functionality is key to Costco's operational efficiency and customer service.

The focus on membership is foundational to Costco's business model, emphasizing the uniqueness of its shopping experience compared to traditional retail stores where anyone can shop without membership requirements.