The 2011 Washington minimum wage for employees is $8.67.
If your salespeople worked solely on commission, they would probably be "independent contractors".
Contracts can have almost any kind of terms the parties agree on.
As a business consideration, you would probably want to treat the people who work for you well so as to motivate them to perform well and to retain them so as to avoid the cost of training new personnel. It is also probably a good business strategy to try especially to retain the best personnel possible.
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