Government Procurement Case of the Dongfeng Single-Cab Sewer Cleaning Truck (Blue License Plate, 5 m³) in Kunming: Analysis and Solution Interpretation of Reputation-Driven Procurement In Southwest China—especially in Kunming, a subtropical highland monsoon climate city—municipal sanitation vehicles face unique challenges: concentrated rainy seasons, high humidity, and intense UV radiation, imposing exceptionally high requirements on corrosion resistance and sealing component durability. Recently, a municipal sanitation department (hereinafter referred to as 'the client') successfully procured a batch of Dongfeng single-cab sewer cleaning trucks (blue license plate, 5 m³) through referral from an existing customer, with positive post-delivery feedback. This article uses this case as a benchmark to analyze the trust chain underlying reputation-driven procurement and to explain how Chengli Special-Purpose Vehicles optimizes its products and services for humid, hot environments. I. Case Background: From Referral by an Existing Customer to Formal Procurement The client is responsible for sewer cleaning and road silt removal across certain urban districts and surrounding townships in Kunming. Its existing sewer cleaning vehicles were severely aged, and most were yellow-plate models, making them inconvenient to operate on narrow streets in older urban areas. It urgently needed to supplement its fleet with blue-plate sewer cleaning trucks. During the pre-procurement phase, the client evaluated multiple vehicle models via public tender information but struggled to balance 'budget control' and 'vehicle durability'. The turning point came from an incidental conversation. Last year, the client’s supervisory authority had purchased water-sprinkling trucks and vacuum sewage trucks from Chengli Special-Purpose Vehicles. After one year of operation, they were deeply impressed by the nationwide warranty service for the Dongfeng chassis and the durability of the superstructure components—particularly the anti-corrosion coating on the tank body. A remark from the existing customer—'Chengli trucks have not rusted on the tank body nor experienced aging or deformation of sealing strips—even after three years in Kunming’s humid environment'—prompted the client to proactively contact Zhang Yue, Sales Manager at Chengli Special-Purpose Vehicles (Tel: ), requesting a detailed proposal for the Dongfeng single-cab sewer cleaning truck (blue license plate, 5 m³). Following technical consultations and an on-site inspection, the client ultimately procured three Chengli-branded sewer cleaning trucks, each priced at approximately RMB 320,000 (based on publicly available tender data and local procurement practices), keeping the total budget within RMB 1,134,000. The vehicles have now been delivered and are primarily deployed for pre- and post-rainy-season cleaning of drainage channels and transportation of road silt. II. The Trust Chain of Reputation-Driven Procurement: How Existing Customers Become the Most Credible 'Sales Ambassadors' In this procurement, the recommendation from an existing customer played a decisive role—a result of over a decade of reputation building by Chengli Special-Purpose Vehicles. Specifically, the trust chain operates as follows: Trust Origin: OEM Chassis + Lifetime Superstructure Service. For its previously purchased water-sprinkling truck (Model CLW5070GSSD6), the client experienced a minor chassis fault during operation, which was resolved within 24 hours under Dongfeng’s nationwide warranty system. Additionally, Chengli guarantees lifetime service for the superstructure, with spare parts shipped directly within 24 hours. This 'chassis assured, superstructure covered' model instills strong user confidence. Critical Pain Point: Corrosion Resistance and Sealing Performance in Humid-Hot Environments. Kunming’s climate is highly humid, with a rainy season lasting up to six months. On standard vehicles, tank coat