I am trying an approach to lead generation for SMBs.

I'd like to verify these small business owners who sign up, so for example if Sally's Holistic Yoga wants to sign up, then Sally would make an account for her business.

However, I could manually verify this information somehow by calling them or whatever else, or there may be some API or service I could use to do this for me.

that being said, I've never done this kind of thing before.