Delays, excuses, and archaic business practices leads to frustration and chaos. It's easier and less risky to send your parts to a place that is run by professionals. And the owner will talk your ear off about his personal life and all his gripes.
I had to wait an extra 3 weeks for the bumper I dropped off in January, which caused me to miss the Barrett Jackson auction. When I came calling for the bumper, I was told they were getting slammed and couldn't keep up. That's information you should tell your customer before they leave their parts, or at least before they drive 25 miles to pick them up.