Thanks for your kind advise. We will try to talk in person with the owner first, and if he still refuses to honor the payment, we will follow up with an employment lawyer. To answer Christine point, yes I was referring to an unlicensed building contractor case a friend told me about and thought it was a general rule that lack of license meant no obligation to pay. I'm pretty sure a drafter doesn't need a license. An architect does, an interior designer too. Anyways, I will check with an attorney if we will get to that point.
Thanks again for all your answers