Dimensional weight - Multiple quantity orders

[jrw36]

This is a defect in eBay software or programming.
I recently sold four sterilization containers to a customer in Japan.  Each item weighed in at 8LBS and 24x13x7.5". So the package was 32LBS and 24x13x30". But she shipping cost FEEbay quoted my customer was calculated at 32# 24x13x7.5"!
If the package was going across town via FedEx it wouldn't be a big deal, like $5 difference (Priority $30 diff) but Japan, we're talking about $100 discrepancy. Add in the 13% commission on the shipping paid by the customer and it cost me $200 to ship an item but received only $87. The sale was $240, minus 17% (international conversion, FVF & promo) = $86 net after shipping and fees, minus the cost of items of $80 >>
I made $6 on the deal (which I probably spend on fuel and packaging) while FEEbay made $58!
Commissions on shipping and SALES TAX is another complaint for another day - But just a hint at what I'm getting at >>> Anybody remember when eBay started charging commission on shipping? They had good reason to do so because so many people were selling their beanie babies for 99 cents and charging $50 shipping so they would only pay commission on 99 cents. Punishing us all for the unscrupulous behavior of some sellers wasn't right but they had a legit reason for the charge... But now, with most shipping being done through eBay the reason for the charge largely doesn't exist now so neither does the original reasoning for it. Then there is one that really bothers me - Sales Tax! Why should we pay a commission on sales tax? Processing fee, yes but FVF? That's theft IMO!
So charging FVF on shipping charges when the reason they used to warrant the charge in the first place no longer exits is bad enough (but imagine them giving up something they already have). 
And charging a commission on sales tax is just crazy!

[wooden_flower]

When eBay started payment processing, they lowered the total % compared to what we paid when we paid both eBay and paypal, so that they could apply a simple combined rate on the total from the buyer.  If they changed it to not charge the fee on the tax, the % would just be higher, so I prefer the simple math of using the total.

Combined shipping has always had an issue on package size. There really is no simple way to fix it, since adding the dimensions together isn't always the correct answer either.

Since you use calculated shipping, you could set your calculated shipping rule to not offer a combined discount.  If the problem only applies to a few items, I'm sure you can find a creative way to cover the extra cost in your pricing structure, or handling cost, etc.