Imagine opening a shopping app and seeing a $79 price for an item while someone across town sees the exact same product for $69. The difference may not be a sale, location-based tax, or membership discount, but an algorithm testing what each shopper might tolerate. That possibility is putting personalized pricing under a brighter spotlight as retailers gain increasingly sophisticated tools for analyzing shopping behavior. For consumers, the important question is no longer simply whether a price looks reasonable, but how that price was determined.