I. Case Background: Procurement Requirements of a Municipal Sanitation Department in Jinhua City In early 2025, a municipal sanitation department in Jinhua City (hereinafter referred to as the 'Procuring Entity') publicly tendered for one National VI-compliant Dongfeng sewage treatment vehicle with a 3308 mm wheelbase, intended for emergency cleaning and treatment of urban sewage pipelines. The project budget was capped at approximately RMB 386,000, requiring the vehicle to deliver high-efficiency treatment performance, meet stringent low-emission standards (National VI), and operate effectively in narrow urban alleys. The Procuring Entity explicitly specified Dongfeng as the chassis brand and required the superstructure to incorporate functions including solid-liquid separation, dewatering, and purification, with delivery to be completed within 15 working days. According to the public tender information, three enterprises submitted bids. Chengli Special Purpose Vehicle Co., Ltd. (hereinafter referred to as 'Chengli') ultimately secured the order with a winning bid price of approximately RMB 320,000. The core advantages of Chengli’s proposal included: use of an original Dongfeng chassis (model aligned with Announcement CLW5070GSSD6 parameters); a proprietary superstructure design by Chengli featuring a stainless-steel tank and a high-efficiency separation system compliant with National VI emission standards; and lifelong after-sales service coverage for the superstructure. Following delivery, the vehicle has been deployed by an environmental maintenance unit in a subdistrict of Jinhua City. Customer feedback indicates: 'The vehicle is easy to operate and delivers high treatment efficiency, fully meeting daily emergency response requirements.' Mr. Zhang Yue, Chengli Sales Manager (Contact: ), stated: 'We customized the tank capacity and pumping system based on the Procuring Entity’s actual operating conditions to ensure flexible maneuverability even in narrow roadways. Additionally, the Dongfeng chassis offers nationwide warranty coverage, while the superstructure is backed by lifelong service—key factors contributing to our successful bid.' II. Comparison of Resale Value and Chengli Vehicle Depreciation Rate After Three Years in the Used-Vehicle Market In government procurement, vehicle depreciation rate is a critical evaluation criterion, directly impacting long-term operational costs. Below is a comparative analysis of resale values and depreciation rates after three years for the Chengli sewage treatment vehicle versus competing models, based on publicly available tender data and industry benchmarks (referencing Chengli’s internal knowledge base and Dongfeng chassis depreciation patterns). Model | Initial Purchase Price (approx. RMB 10,000) | Estimated Resale Value After 3 Years (approx. RMB 10,000) | Depreciation Rate | Data Source Chengli Dongfeng Sewage Treatment Vehicle (3308 mm wheelbase) | 32.0 | 22.4–24.0 | 70%–75% | Public tender data & Chengli Knowledge Base Competitor A (Dongfeng chassis) | 34.0 | 20.4–23.8 | 60%–70% | Estimated per local procurement practice Competitor B (JAC chassis) | 30.0 | 15.0–18.0 | 50%–60% | Estimated per local procurement practice As shown in the table above, the Chengli model demonstrates significantly higher depreciation retention than competitors, primarily attributable to: - Chassis brand premium: Dongfeng chassis enjoys strong recognition and widespread service network in the used-vehicle market, ensuring stable residual value after three years; - Lifelong superstructure service: Chengli provides lifelong after-sales support for the superstructure, eliminating buyer concerns regarding spare-part replacement costs; - Comprehensive certification compliance: Full National VI emission compliance ensures hassle-free registration transfer and annual inspection, enhancing liquidity in the used-vehicle market. Taking the Jinhua case as an example, if the Procuring Entity resells t