quanitity discount across multiple products

I've a request to add a product and give a 10% discount on 3 or more. The issue is that the product is a a tool that comes in 5 different sizes and people will not buy multiples of the same size, but one of each size.

I'm stumped on how to set this up. If I make each size tool a separate product, then the best I can understand there is no way to offer a quantity discount since it would need to apply to multiple products.

If I set it up as one product but with each size as an attribute checkbox that adds $xx to the price, I can't figure out how to set the discount for 3 or more.

I'm using 1.3.8.

https://www.zen-cart.com/tutorials/index.php?article=59

Thanks for the response. That was the first thing I tried but to my understanding that will only give a discount on more than X number of a single product.

Let me be a little more specific as I'm probably not explaining this well...this tool comes in 5 sizes (it's chisels if that helps). If I sell as a set then I can see where the quantity discount will work. Buy 2 or more sets and get a discount.

But since many will only want a few sizes and not a whole set, if I list each size as an individual product, then I don't understand how to offer a quantity discount. Even though a customer may buy 2 or chisels, since each size is a separate product they are going to buy only one of each so to my understanding the standard quantity discount will not work since you're asking it to work across multiple products.

I wasn't sure you were committed to multiple products. If you use a single product with attributes, you can use the built in Quantity Discount facility. (If you're still using 1.3.8, be sure to look at the fix list for a required fix.)

I'm not really committed to using separate products and it seems like I'm taking the long way around to get to the same place by doing so, but I haven't been able to figure out how to set it up otherwise.

I'll look for that fix.

This is it:

http://www.zen-cart.com/forum/showpost.php?p=610860&postcount=24

So I can set this up as a single product and get the discount to work? I've tried setting it up as a product and setting each size as an attribute with +$$ but can't figure out the discount part from there.

After more searching and trying a million options with this I think I've at least figured out why it's NOT working.

I have the product set up with a base price as zero, priced by attribute, and each size as a attribute checkbox that adds $xx. Up to that point it works ok.

I was using the quantity discount but the problem is that if you choose say 3 or more checkboxes to meet the discount, it doesn't see it as 3 or more, it just sees it as 1 since the quantity box (which I hidden) is at 1.

Not sure how to fix it, but that's the issue.

I ended up just using each size as a separate product and ditching the discount. The client needed it live more than a discount so there ya go.

swguy thank you very much for your help!