What is a multipack listing?

An Amazon listing that sells several units as one - mind the arithmetic.

A multipack listing sells multiple units of a product as a single purchase - a 3-pack of soap, a 6-pack of snacks. The Amazon price covers the whole pack, so the sourcing arithmetic must multiply your buy cost by the pack size before any profit calculation.

Missed multipacks cut both ways: match a single unit against a 4-pack listing and the deal looks four times better than it is; spot that the retail 2-pack maps to a single-unit listing and you have found margin others miss. Reading the pack size in the listing title is a habit worth building early.