Simple. Everyone that doesn’t have a rental certificate should just board up the house and protest their taxes.
It shouldn’t surprise anyone that Nazis elected to positions of power within local governments behave like Nazis. I note that this is a college town, these people don’t want college students renting houses in their neighborhoods. College towns tend to reflect the Nazi attitudes of the staff and faculty and are among the worst offenders when it comes to restricting liberty and property rights.
As a board member of a condo complex in Colorado, I get asked by underwriters what the percentage of owner occupied units are.
I decline to answer. There are many shades of grey. Is the occupant related to the owner? If so legally only, or also by blood? Does the occupant pay rent? If so, is it market level rent? How can we verify the payments?
Until these questions are answered, there is no reliable way to make a determination.