I. Procurement Background and Real-World Application: Sewer Cleaning Truck Selection for Shenzhen’s Humid-Tropical Environment In summer 2025, a municipal sanitation department in Shenzhen planned to procure a batch of blue-license-plate sewer cleaning trucks for routine desilting operations in urban stormwater pipelines and underground channels. The procurement requirements were explicit: vehicles must be blue-plate registered (drivable with C-class driver’s license), built on a Dongfeng double-cab chassis, and equipped with a tank having an effective capacity of 3 cubic meters. The budget was capped at approximately RMB 287,000 (based on publicly available tender information). Shenzhen, located along the southern coast of China, experiences year-round high temperatures and heavy rainfall, with an average annual relative humidity exceeding 80%. During the rainy season, operational frequency and workload are exceptionally high—posing stringent demands on anti-corrosion coatings and the durability of sealing components under humid-thermal conditions: standard carbon-steel tanks tend to develop internal rust after just one monsoon season; sealing components age rapidly under high temperature and humidity, leading to vacuum system leakage and reduced suction performance. Previously, this unit had procured sewer cleaning trucks from other brands; however, within less than two years of service, issues such as bottom-tank perforation due to corrosion and hydraulic cylinder leakage emerged. Consequently, this procurement specifically emphasized: “The interior of the tank must undergo enhanced anti-corrosion treatment, and all sealing components must be certified for durability in humid-thermal environments.” II. Identifying and Countering the “Package Trap” Pricing Strategy A total of four suppliers submitted quotations for this tender. Among them, two adopted the typical “package trap” approach: their quotations listed only generic items—e.g., “standard tank,” “standard sealing components,” and “standard hydraulic system”—without specifying material grades, manufacturing processes, or component models, and claimed an “all-inclusive price” of approximately RMB 198,000 (per market reference data). Deconstructing the Trap: • Low-price Bait: Quoted RMB 30,000–50,000 below the normal market rate to attract attention. • Vague Specifications: Failed to disclose tank steel plate thickness, anti-corrosion process, or brand/grade of sealing components for humid-thermal resistance. • Post-Award Add-ons: After winning the bid, cited “Shenzhen’s humid-thermal environment necessitates upgraded anti-corrosion coating” or “high-temperature-resistant sealing components must be added,” thereby imposing additional charges—often pushing the final delivered cost above RMB 287,000. • Glossing Over Critical Details: Emphasized the “Dongfeng chassis” brand while omitting key technical parameters of the superstructure (tank, vacuum pump, hydraulic system). A procurement manager from the municipal sanitation department recalled: “We’ve encountered similar cases before—after awarding the contract, the supplier claimed the standard tank would rust within six months and insisted on adding hot-dip galvanizing at extra cost, otherwise refusing warranty coverage. This time, we mandated that all bidders submit detailed anti-corrosion process documentation for the tank and certified test reports verifying sealing component performance under humid-thermal conditions—or face immediate disqualification.” III. Chengli Special-Purpose Vehicle’s Transparent Configuration Proposal Chengli Special-Purpose Vehicle (Model: CLW5070GSSD6, per MIIT announcement parameters) submitted a fully transparent configuration list in its tender submission, explicitly specifying brand, material, and process standards for every core component: Configuration Item | Typical “Package Trap” Quotation | Chengli’s Transparent Quotation ---|---|--- Tank Material | “Standard Carbon Steel” | Q23