Currently, I have multiple vendors and charge shipping by flat rate and per weight/per item.

Since no multiple vendor shipping module exists (to my knowledge), I treat myself as the vendor and contact the others as needed.

This is great when buyers order no more than one product per vendor. But when they buy more than one product from a vendor, vendors can save on costs by bundling their products and I'd like to pass those savings on to my buyers. Any ideas on how I can do this?

And if anyone has any suggestions for multiple vendor shipping modules, I'm all ears (did the search, no results yet )

Thanks for the help!