You can rather easily become
the obvious expert of indoor gardening by creating a website and/or blog with lots of useful, free information. People will buy stuff from a friendly obvious expert who they feel can help them succeed with their dreams of indoor gardening.
Many vendors now make full use of the Inet. Every day more manufacturers recognize the profit potential and FUN of doing business with small businesses.
As for manufacturing, it's a Chinese world. In my dreams Detroit's big auto makers devolve back into a hundred separate, smaller, agile, auto manufacturing companies. About a hundred separate auto makers called the Great Lakes region home back in the early days. Before big bloated bureaucracies ate everything in sight.