Kansas City Earnings Tax on Rental Income

I'm a retiree living on soc sec and savings and I have a rental in KCMO and live in KCMO.

Also a couple rentals outside of KCMO.

Everything I can find about KC earnings tax on rental income (Eg RD-100) talks about BUSINESS owning rentals, not an individual. 

Examples exist that suggest that many rentals are investment not earned income. 

I'm not an LLC, I don't have a business license, don't fill out a Sched C on federal etc. 

I can't find any definitive documentation that pertains to my case (and many others I suspect)

Would appreciate any clarification you might have.