Shorty,
Microban sells several antimicrobial products the most used commonly used here is a Quat.
I don’t think it’s wise to offer antimicrobials as an upsell unless there is some specific reason to apply them like prior water damage. Most of the antimicrobials on the market have drawbacks like health concerns or damage to carpet protection.
According to our government: There is no such thing as green antimicrobials and the EPA puts them in the same category as pesticides.
I am excited about some of the greener antimicrobials on the market especially the peroxide based products. Currently, hospital grade peroxide based antimicrobials are only available in Europe.