It depends on your State's regulations regarding exterminators.
In California, you don't want to be doing pest control for profit, while being unlicensed.
M-7 for fleas
R Value West
810 E 18th St
Los Angeles, CA 90021
(213) 747-0223
This product is designed to be added to your carpet cleaning solution. However, it's only approved application is for a portable. I don't think you could be concentrated enough through a chem jug/flowmeter unit.
We used to sell this product, until we heard some of our customers were penalized. It is interesting that there is nothing illegal about selling this product to an unlicensed person, nor buying it, or even using it without a license (for personal/consumer use). Where you cross the line is when you actually perform the extermination service as a business. The state rightfully reasons that someone who is doing it for hire must be trained and held responsible for both efficacy and safety.