I want to go to Kunming to buy a second-hand rear eight-wheeled dump truck.

Hehe, buy a second-hand van, right? It seems that there is only a relatively large second-hand car market specializing in trucks in Kunming. You go to Yunnan used car trading center (national level) to have a look. The telephone number is 84 19890, next to Mingbo Furniture Supermarket. I've seen it. Many models, not expensive. Take bus 100 in the small vegetable garden, which is only a short walking distance from the terminal. However, Mingbo has two used car markets. Besides the one I mentioned, the other one specializes in cars. Then don't make mistakes.