Parking More than One RV on a Private Property (Not zoned a mobile home park)
This option is generally not recommended, unless you are a hospital. A hospital might be able to pull it off, but please be realistic that this will take significant time and resources to achieve.
Parking more than one RV on a property will draw attention from neighbors and government officials. So either avoid doing that or be proactive with your intent at your local building department, to receive acceptance.
Your local “Jurisdiction Having Authority” is a specific legal term defining the rules for you. It is typically the county, unless you live within an incorporated city. If you wish to advocate for a specific policy that is not available to you, the building department is NOT the place to do it. You need to contact your City Council or Board of Supervisors and participate in the public comment process. (Here is an explanation offered by the City of Chico. See page 2.)
I’ve volunteered for five years in fire storm recovery efforts. Every community fails in group encampments. FEMA fails all the time in achieving this. This is due to either to the cost to provide utility infrastructure or the liability of having unrelated people living on a property, sometimes both. Even though you can tell people this, there will always be someone who will try anyway.