e-commerce / Cheap Business

The best kind of customer is the one you have before you build or buy anything.
Explore different kinds of promotional avenues, like the ones in this link: https://rafflepress.com/ecommerce-promotion-ideas/
Then, accept the following challenge:
1) Explore, isolate, and explain an industry or business that would take an investment to start and might be difficult to bootstrap for most people (for example - airlines, automotive factories, etc.). 
2) Strategize 3-5 ways you could promote your business and "test the waters" before investing in that business for free or mostly free online. Explore the benefits, drawbacks, and risks of each.

( In less than a page )