We sell audio dramas on a custom basis. That is, we produce a number of shows, and customers can buy any they want - 1 or all.
When they order, we burn the show(s) they've bought to CDs - more than 1 show can fit on a single CD - and put the CDs into a single case. Could be 1 show or 12, on 1 CD or 4 in a single case.
I want to set a single shipping price for the package - no matter how many shows/CDs are in the package - but allow the customer to select the USPS rate. Do I set a separate weight for each show? Or is there a setting to put a single shipping cost on the package no matter which or how many shows they buy, but still do a USPS lookup?