a job that refused to pay me overtime after a year of working for them as the sole employee/manager of the shop.

Wow, like they would force you to work just under the limit to qualify for overtime, or wouldn't pay overtime owed? Because that's straight up wage theft!

I notice businesses that try to be "savvy" by taking shortcuts and skirting labor laws tend to collapse themselves once they run out of employees that are way too good for them and won't put up with it anymore.

Glad you escaped.