Hey Joel, we can't access file:///C:/Users/joeyou/Downloads/episerver_ecommerceguide_final.pdf ;)

Kidding aside, I don't really know where is that recommendation coming from, or why it is there at the first place. I suppose that the reason behind it is to make sure the customers get the best discount possible. 

Later version of Commerce should have made sure the price is never negative. If you can reproduce the issue, let us know. 

https://www.episerver.no/contentassets/cf632c659b554f77a3683e855d6dc8d0/episerver_ecommerceguide.pdf (P53)

For most of the cases, the behavior is correct, In UK market this kind of discount is norm, within a 3 for 2 entry, If I have a coupon for 5% off on my order over £50, It should work. we don't have negative price issue for our promotions anymore with this combination of promotions.

But... the link works for me... why shouldn't it work for you???

(I meant to link http://www.episerver.com/learn/guides/a-guide-to-mastering-ecommerce/ :P)

Of course the customers should get the benefit from both order and entry level. But Quan, the prices would still be the same? Say you have 3 items in your cart, á $90, $100, $110, totalling $300. You have 3 for 2 and 10% off.

If order comes first: $300 -> $270 spread out ($81, $90, $99), then minus $81 leading to the total of $189

If entry comes first: $300 -> $210 then 10% -> $189

So for the customer it becomes the same.

But this begs the question, you say that negative prices is fixed. Does that mean that the 10% will be less than 10%, or does it now spread the 10% unevenly between the lineitems, to make it 10% on the order, if one lineitem has price 0?

Nevermind, I got this twisted in my head... 

I don't remember specific details (the pricematrix is quite (read, very) complex and I don't follow every change) - but I would say it will be the latter - the free item will receive 0, and the 10% will be distributed to the remaining items. Any negative price should be considered as bug. 

We talked about having a  "Order Level Discount Amount" field on OrderForm, that would simplify things quite a lot - but I don't remember the direction of the discussion. It might be not possible due to breaking changes. 

I guess the issue with introducing such a field on OrderForm would be that you postpone the distribution of the discount to a later point where someone else have to implement it.

I think most countries require you to show a VAT breakdown by rate on the receipt, at which point the order level discount amount have to be distributed on the line items to get a corresponding vat rate. Unless of course all your items you sell all have the same vat rate then it is a non-issue.