Oh man, that's the worst feeling. I had a great client who was always on time, then one check just... didn't work. It was like a bad magic trick. My own bank charged me a fee and everything. I gave them one free pass because stuff happens, but I also started making them pay upfront for materials before any new work. If it happened a second time, I'd probably have to hit pause on the project. It just shakes your trust.

My buddy ran his shop that way for years, just eyeballing the belts. Then one gave out on a Friday afternoon and took the water pump with it. He lost a whole weekend of work waiting on parts and paying for the tow. The repair bill was way more than a set of belts would have cost.

@the_matthew's fix shows how real solutions often mean going deeper than the surface problem.