Two stainless steel cleanroom panels can look identical on the RFQ but land 30–90% apart at the dock. The gap is rarely margin alone — it sits in stainless grade (201 / 304 / 316L), face thickness and tolerance, core type and density, surface finish (2B / No.4 / BA / mirror), bonding method (manual glue-up vs continuous hot-press), edge sealing and project-level customization. This module decodes the cost stack for overseas procurement engineers so a GMP, food-washdown or hospital OR spec can be priced on facts, not on PDF photos. SAMZOON, a Foshan source manufacturer, anchors the walkthrough with free samples, custom widths/cores, and South China purification project QC.