I. Project Background: Leadership Requirements Raised — In July 2025, the head leader of a district Urban Management Bureau in Guilin City proposed at a special meeting on municipal infrastructure maintenance that sanitation, greening, and drainage work teams within the jurisdiction had long relied on aging trucks and temporarily leased vehicles, resulting in slow maintenance response and disorganized dispatching. Particularly during the plum rain season, Guilin’s annual rainfall exceeds 1,800 mm, and the high-temperature, high-humidity environment has caused severe chassis corrosion and aging/sealing component leakage in existing vehicles, significantly impairing operational efficiency. The leader explicitly mandated: “A batch of service vehicles with excellent corrosion resistance, superior sealing performance, and suitability for high-frequency rainy-season operations must be procured, with a budget capped at approximately RMB 344,000, referencing publicly tendered information.” Subsequently, the bureau’s municipal sanitation department formally initiated the procurement process, planning to acquire 12 Foton Fengjing service vehicles for daily inspections, equipment transportation, and emergency repairs. II. Internal Selection Discussion: Focus on South China’s Humid-Hot Environment — During internal discussions, the procurement team prioritized three key criteria: (1) chassis anti-corrosion capability—Guilin’s relative humidity remains above 80% year-round, and frequent road-sprinkling exacerbates rusting of standard galvanized steel plates; (2) durability of sealing components—doors, windows, and electrical interfaces must resist water infiltration during rainy-season operations; and (3) engine and air-conditioning systems capable of withstanding frequent start-stop cycles and prolonged idling. After comprehensive comparison, the team shortlisted the Foton Fengjing G7-series service vehicles, whose chassis features electrophoretic anti-corrosion coating and standard waterproof sealing strips. However, further research revealed that some suppliers’ models lacked specialized optimization for South China’s humid-hot climate. At this point, Ms. Zhang Yue, Business Manager of Chengli Special Purpose Vehicle Co., Ltd. (Tel: +86 ), proactively contacted the procurement team and proposed a customized solution. III. On-Site Inspection of Chengli Factory: Witnessing Anti-Corrosion and Sealing Processes Firsthand — In August 2025, a three-member procurement team visited Chengli Automobile Industrial Park in Suizhou, Hubei Province. At the factory workshop, they focused on inspecting the painting and final assembly lines. Chengli technical staff explained: “For users in South China, we apply an additional underbody armor coating atop the Foton Fengjing chassis—exceeding 200 microns in thickness—to effectively isolate moisture. All door seals are upgraded to silicone rubber, offering aging resistance across temperatures from -40°C to 120°C. Furthermore, to meet demands of high-frequency rainy-season operations, anti-mold filters are installed in the air-conditioning evaporators.” The inspection team also conducted an on-site sealing test—spraying doors continuously with a high-pressure water jet for 20 minutes—revealing zero water ingress into the cabin. The team confirmed on the spot that this customized solution would significantly extend vehicle service life in Guilin. IV. Contract Signing and Delivery: Delivery of 12 Service Vehicles and User Feedback — In September 2025, both parties signed the procurement contract for Chengli-modified Foton Fengjing G7-based service vehicles (model reference: CLW5030XLCB6 or similar certified variants). The unit price was approximately RMB 98,000 (per publicly tendered information), bringing the total contract value—including tax and all-in delivery costs—to roughly RMB 1,176,000. By early October, all 12 vehicles arrived in Guilin. Following delivery, the procurement team randomly