To me, there are two questions here.
1- Do you share a proprietary design with someone who is selling for you? I can't answer that one for you, but if we have a new design, unless it was created specifically for a certain customer, we want to sell as many as we can, to whoever wants them. That, to me, is the whole point of being in business.
2- Do I sell this design and risk errors being made by the seller? I don't see how this is any different than any other product you sell to them. The same opportunity for error (spelling, dates, etc.) exists on any order they sell for you. Your reputation should be no more at risk with this product than any other. If they submit an order with errors, then the mistake is theirs and the responsibility rests on them to have it corrected at their cost. Whether you offer a discount for a re-do is up to you.
Is there something about the design that would make an error more egregious? Maybe I'm missing something here.
If you don't produce the product for them, would they look for another source? Unless you've had some custom piece made for your design, it's really kind of hard to imagine something that another shop could not duplicate. If you produce it for them, they will have no reason to look for other sources.
Always keep in mind that by helping them sell your products, they begin to build a customer base looking for those products. The inquiry about your proprietary design is an example of this. You said your name was on the back of everything, yet the customer came to the sewing shop to get the product made. Since you are selling to them at retail, their prices are higher than yours and their costs are much higher than if they produced it themselves. I predict they will be making their own within the next 12 months and will become your competitor.
You said you're "mostly happy" with the relationship so it's not perfect already and they may not have any problem going into business against you. They are located closer to the base and you're helping them build their customer base in your type products. I think it's inevitable that they will enter the industry, especially with our entry barriers so low.
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Sam Varn, CRM
Awards4U
President / Zen Master of Recognition
sam.varn@awards4u.com850-878-7187
Tallahassee, FL USA
www.awards4u.com------------------------------