Does the Customer Get to Approve Designs?

Just state your terms and working conditions upfront when the order is placed. I can see why they might have been confused here if you said you were going to show them work in process - perhaps they interpreted that to mean they would have some choice. Anyway, when I had my shop, I would do custom samples but they were charged out as a regular order - never given away for free, and always done well in advance of production of the actual order. Otherwise, I wouldn't allow any choice. I stated these terms clearly in written contracts for large orders.

Ok thanks. But for the moment i am not working with contracts.  So to avoid the impression that showing a preview is implying choice, I could say they will be ready on x date based on their description. ?  Basically, how do I say you will get what I design based on what they described?  

I would recommend putting large orders in writing (even if via email) so there can be no misinterpretation. That's probably the reason for the confusion.

Just say what you said: I will design based on design discussions; customers will not see advance designs or get pre-approval of designs unless they pay for advance design work.

That is perfect. Thanks. Fortunately turned turned out ok but I learned a lesson here.