You can learn the greatest things from the most unusual places ....
If you saw the movie "Goodfellas," you saw a film based on the biography "Wiseguys." It is the story of a half-Italian kid, growing up into a fringe role in organized crime.
His mentor would often front the money to start a small business, such as a restaurant - then show up every week to collect his payment. According to the author, the same story played out again and again. After a few timely payments, the guy would come up short one week. A drop in business, unexpected expenses, all manner of stories. Some might even have been real. Yet, the response of the mobster was always the same: "Gee, that's too bad. Now where's my money?"
I think you see the point here. The whole purpose of working is to get paid. If you don't get paid, you won't be able to continue operations.
That said, be aware of what your local laws allow. For example, the fine print of our contracting law can allow the customer as much as 30 days to pay (depending on circumstances). You may not just 'stop work;' you need to have a 'legal reason.' Since the Contractors' board is not very explicit as to what they consider a 'legal reason,' you don't want to act rashly. A call to your board might be the best dime you'll ever drop.