Have them fill out an application form listing their previous place of employments, references, etc.

From your question's verbiage, it sounds like theyre trying to verify the length of self-employment history, probably to meet either the two-year or five-year marks.

Agents are typically 1099 self employed contractors.

You’re a family office and/or employ advisers trying to earn their salary and/or investing as 100% owner of a TIC (or JV) and can maintain continuous pre-tax compounding even after exiting a position.

Diversify your study by including communities with employment growth, schools, and low crime rates.

Now I have other concerns.Sure, I've been self-employed in the business now for two years and my wife just quit her main job, but we're not slowing down now.

However it doesn't change the fact your name will be forever be listed on a docket and its one more thing you have to explain to banks, financing companies, employers etc.

Any new employers in the area? 

At the time I was legal counsel at REIT  as my primary employment and the SFH's where viewed as a passive investment.

Others employ a BRRRR method or do wholesale deals/flips to have cash to invest long term.