Seriously. You can start with one bag of seed and a few plastic buckets and sell to local businesses (especially organic businesses and asian stores since they sell larger quantities) and scale up from there. Inventory isn't a huge problem since it only takes 72 hours to grow the sprouts, and you can buy the seed by the 25kg bag.
Obviously, I'm simplifying things, but honestly it's a business that's incredibly easy to get into, resistant to non-local competition due to the perishability of the sprouts, and if you can 'get it right', you can definitely market on quality