TV investigators do get results. I like all these suggestions, but the best way to be effective is to spread the word of his bad behavior toward a senior citizen. What a putz! You need to help put him out of business. A policeman escort to pick up your machine is a good idea. Use them to your advantage. Big men with you are also nice, but not as effective. Next time when the hair raises on the back of your neck, run, don't walk to the nearest exit and find someone else to service your machine.