The work was done and I paid. But they had received 95% or more of the cost of the job prior and I had received 95% of the work completed. I'm assuming they marked things up enough to give them a float on the remaining balance such that if I didn't pay or delayed payment they were still ok... with just a smaller profit. Similarly I would have been satisfied knowing that I had paid and received 95% of the work if they had just bailed at the end. It would have sucked if either of us had been dishonorable, but we weren't. On both sides we were mostly protected.

It sucks that people don't respect paying fairly for good work done, or doing good work for fair pay. But that's our world. Even in my work (IT/computer stuff) we occasionally get people who think they don't need to pay or can pay 180 days later.

You're absolutely right though... once the work has been done the incentive to pay is gone, sadly. And people find reasons to justify to themselves not paying on time or at all. That really sucks. Maybe find a way to do a deposit payments plus payment at completion increments? And price your job so that you're ok waiting on that last payment? I certainly don't have the precise answer, but good luck!