Quantity Discounts for 1.3

[HeleneWallis]

Okay, disregard the last--I found the version for Zencart. But I don't see how I can use it to allow set prices for a quantity purchase.

[swguy]

There's one for ZenCart too. Please contact me through my site.

[kernheimer]

Hi Scott, probably my english is the bummer, but i can not find how to achieve this:
i have different prices for quantity, but not all items have the same price.
so idealy i would like to see my discounts as a sliding scale discount.
is that possible also?
if not, do you have a sollution

[swguy]

You would probably be better off with the built-in quantity discounts then, which allows per-item configuration of the discount.

[flyvholm]

I've had the embarrassing situation that my Zen Cart made obvious calculation errors in some situations, specifically when Quantity Discounts worked in combination with a discount coupon. I finally tracked down what seems like a bug (at least it worked as such for me). In includes/modules/order_total/ot_quantity_discount.php, function process() subtracts the discount from and adjusts the tax amounts in the global $order array. However, $order stores both a subarray of the separate taxes ($order->info['tax_groups']) and a total sum of those taxes ($order->info['tax']). In function process() the subarray is adjusted, but the total sum isn't. This can be fixed by adding a line...

               $order->info['tax'] -= $od_amount[$key]; 

...just after the line with the same adjustment to the subarray $order->info['tax_groups']. I hope this may help a few others avoid what I've just been through. Thanks a lot for this module btw - the user exits are brilliant for me, making it easy to set up customized discounts that couldn't be done via the admin interface.

[swguy]

Thanks for posting this. What are your settings for admin-modules-order total-Quantity Discounts, and do you have multiple levels of tax? I'm just curious about why I haven't seen this before.

Later update: note that shopowners who recalculate tax should set the sort order for native discounting modules *above* (i.e. lower than) my modules. Otherwise they will need to make the changes described in https://www.thatsoftwareguy.com/zenc...resorting.html.

[flyvholm]

Include Tax: False
Re-calculate Tax: Standard
Sort Order: 200 (between Sub-Total and Discount Coupon)

Only one tax in my case (EU VAT). The ot_tax module only uses the subarray $order->info['tax_groups'], so the problem isn't seen in basic use. Perhaps combining Quantity Discounts with coupons is rare, but given how much this module has been used I'm also surprised this issue hasn't surfaced before.

[EZorb]

I am installing 1.5.5e and need Quantity Discount for 3, 6, and 12 items. I only have 3 products to sell. The discount works great on each product. I also need to give discount on mixed. If customer buy's 3 different products they still would get a discount. Can the built-in quantity discount mod provide mix product discount? If so how do you set it up?

[swguy]

Use the Quantity Discount mod and set Discount Basis = Total Items in Cart in admin-modules-order total-quantity discounts.

[Dave224]

I have a problem with Quantity Discounts and Edit Orders. When I purchase an item eligible for quantity discounts on the store-side, everything is fine. But when I edit that order in the admin, everything is correct except the order total. It is too low by the tax on the quantity discount amount. I have been discussing this issue on the Edit Orders support forum, beginning with post #1195, but I'm stuck. Has anyone successfully integrated these two plugins successfully? Any hints would be gratefully appreciated. ZC v155e, Quantity Discounts v1.12.1, Edit Orders v4.3.1.