You've had one complaint in 3 years? I'd say you are doing pretty well. To me, what matters is how well are you doing overall. Are you making good money? If yes, then keep doing what you are doing, your instincts are good, don't change your approach to business because of one customer. If you're in business, you're going to get taken once in a while, that's all there is to it. Happens to me. I run my own business (not detailing). I place a certain amount of trust in customers, they appreciate it, they reciprocate. This also results in me getting screwed over occasionally. The question is, what's best for my long-term revenue? Plan A: Gains me 8 long-term customers, but one screws me over. Plan B: Gains me 4 long-term customers, but nobody screws me over. I choose plan A, it's best for business overall. But everyone has to do what suits their personality best.