1. research the cost of producing a production-ready physical product. You need millions of up-front investment and a couple of years of funding.
2. research how a toaster is sold. Spoiler: you need attention and access to a target audience. What would be your customer acquisition cost to sell 100K units?
3. what is the customer lifetime value of a person who bought your toaster? Spoiler: your competition might be a 10 USD made-in-china piece of crap, so people a willing to spend 25 USD on something that is not dead-on-arrival. How much do you need to charge for a made-in-USA toaster? 99 USD? 299 USD?
4. how much do you need to spend on branding and marketing to get the value of "made-in-USA" attached to the toaster? 10M? 50M?
5. how will your life look like, when you manage to pull this off to sell 10K toasters? My assumption: it will be a constant nightmare/living hell, as you now have a mountain of dept, high running costs and many people asking you to sell the next 100k toasters...