Prototyping your product domestically offers many advantages.
With domestic prototyping you can get faster real time development, feedback and testing, and save a lot of time and headache.
Certain product categories lend themselves well to prototyping in the USA, such as new inventions, bags, gear, etc.
With design development here in Utah , your product can be developed to a productionized state, and along with providing technical specifications and BOM/a technical pack, it will make sourcing and potential overseas manufacturing much easier.
The process of prototyping does take time, and with typically a couple of iterations, your product will be in a much better position to be manufactured.
The process can begin with the objective goals, solutions, market, pricing tiers, and design aspects of the product. Then with some creative brainstorming and sketching, a good direction can be determined for design and materials. As the process continues the product will improve to a state where you have a minimum viable product ready for test marketing and manufacture.