A 600×600 LED panel quotes anywhere from six to nine dollars. The housings look the same and the spec sheets can read identically. Where does the money go?
Start with the bill of materials. The cost sits in the aluminium frame, diffuser, light guide plate, back plate, LED bars and driver. Labour on an automated SMT line is under ten percent, so cheap labour does not explain the spread.
Aluminium is first. A 0.6 mm frame against a 1.0 mm frame is 40 percent less material, and the price shows. Thin frames feel flimsy, deform in transit and conduct heat poorly. Alloy matters too, 6063-T5 is standard, recycled aluminium is cheaper and weaker in both strength and surface finish.
Second is the diffuser. PS is cheap with mediocre transmission and yellows over time. PMMA costs more, transmits better and resists yellowing. The gap runs to 10 or 20 percent of total cost.
Third is the driver. Topology, capacitor brand and isolation can double driver cost. A luminaire that is two or three dollars cheaper is usually cheaper here.
Fourth is packaging and freight. Panels are bulky and ship by volume. A tighter carton design can add 20 percent more units per 40-foot container, which is real money per unit. It gets ignored in comparisons because everyone looks at FOB.
Then a hidden one: yield. A factory running 85 percent first-pass yield carries the rework cost into its price. A quotation that looks unusually low is either downgraded material or a yield problem, and both surface later.
The practical routine: build a four-column table, aluminium thickness, diffuser material, driver topology and carton volume, and compare line by line. Only quotations that match on all four are comparable.
During audits we measure frame wall thickness, read the diffuser marking and open the driver. Ten minutes of work that explains a 30 percent price gap.