Sounds like you'd have to hack your way around the mixed basket, Chris. Normally, if your customer buys a poster-tube item with media mail items, only one method of shipping can be selected.

I'm hesitant to recommend any approach that disables the checkout button, as with that check-for-mixed-items-and-demand-customer-orders-one-at-a-time hack. To do so is to disrupt the checkout and probably kill sales. It's like the clerk at Wal-Mart refusing to scan one of your items unless you pay for your other selections first, then go to the back of the line and purchase the oddball item separately. (There are exceptions to every rule, as with firearms and ammunition: brick-and-mortar stores in the U.S. are forbidden from selling these together.)

So, what would happen if you gave the pseudo-boat-oar product(s) a mandatory option-attribute called "separate package shipping" or some such -- and priced the attribute to cover your extra shipping expense?

The hacks I'm using on my Shed Kit shop eliminate UPS from the list of available shipping methods when total shipping weight >=800 pounds -- and eliminate common carrier methods when total shipping weight <800 pounds. But I doubt this kind of tweak is appropriate for a store needing to charge for two shipments on one order.

If the options-attributes approach doesn't float your boat, don't give up -- where there's a will, there's a weigh.
Quote Originally Posted by kusogaki View Post
But if I were again, to have a mixed order...will it add the two shipping totals together or would they just ######## heads and throw me an error?