I am also confused. I've lost over $70 by selling my posters; one stolen in the mail tube, one damaged (both had to be replaced), plus I was matching Scotts price to avoid confusion even when I had tax on each as the printer is in my state. So there was no money being made here.
If you want to share in the profits then you should share in the costs too. I'll send you a bill for your share
When I paid you to do the rendering there was no mention that you owned the rights to these forever and we had no right to reproduce them in any way. If that was the case you should not have given us a poster resolution sized image. You knew what we were doing with them. For that matter, since it's my car in that rendition do I not have the right in how the picture is used?
You make your money by charging us to do these. You certainly don't give them away and it seems like you're always busy and should be making plenty of money on the side with them. If you want to retain control of the pictures then you need to pay us in my opinion.
Jody