Are we paying these commissioned employees properly, or are they owed overtime?

Q: “The Department of Labor’s website says: ‘Employees of a retail or service establishment who are paid more than half their total earnings on a commission basis may be exempt from the overtime pay requirements of the FLSA.’ I understand that this exemption from overtime would apply to employers who are paying commission only for employees who paint cars and get paid a percentage of the sale for each car they paint. I further understand that they also must pay the employee at least one and one-half times the minimum wage and be able to prove they’ve done so by maintaining time records. Is there anything I have missed, or that I am misunderstanding?” – Cristy, North Carolina