An example of a prototype being built in China (simple video): 

This video shows how to make a prototype in China incredibly cheaply, safely, and efficiently.
Send your design to China, and after 10 days, you receive your prototype.
It is now called a prototyping factory in China, which means that this factory can only make prototype products, not mass-production products.
Many prototyping companies in China are now available if you have an idea that needs to be made and implemented.
You can send the file .dxf or .step to the prototype factory and select the material; they will make the prototype for you quickly and cheaply.