Congrats on your potential opportunity!
DRTV can be approached in two ways:
1) A DRTV company buys a product at a wholesale price from you. DRTV typically needs 5-6 times mark up. Usually a cost of $.50 to $1.75 to achieve a $14.95 - $19.95 retail. In this situation, you will need to ensure you can supply approx 1,000,000,000 units a month! YES, you heard right.
2) A DRTV company takes on the item under a licensing deal, they manufacture and distribute into retail, and the inventor collects a negotiated royalty (typically between 3-5%) of the retail price point.
Hope this helps, GOOD LUCK!