Product variant qty and global qty in checkout

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@support,

Here is a nice for you

If I select 3 products for example. Each product I select a qty in the variant.

So Product 1 = 3 x Red @ $9.00, Product 2 = 3 x Blue @ $9.00 and Product 3 = 3 Yellow @ $9.00

So in the cart I would have:

Product 1 Red QTY 3 $9.00

Product 2 Blue QTY 3 $9.00

Product 3 Yellow QTY 3 $9.00

Total Coast $27.00

Now is it possible for the checkout to count the qty which would be 12 and then charge $25.20 as that is the cost in the variant for a QTY of 12.

Is that possible, or totally restricted in the add to cart / product / checkout system ?

Thanks in advance,

MSF

@Nicolas,

Thank you, all the main products are set to "$3.00 for 3; / $2.40 for 6; / $2.10 for 12; / $1.85 for 24; / $1.75 for 50; "
Values are not set in the variants.

So if they select qty 3 from product 1 and then qty 3 from product 3, the cart currently adds the total to $9.00 for each product with a total of $18.00

But as they are all in the same category, can they then add to $14.40 for 6 (based on $2.40 * 6 )

Or do I have to do something really clever with the coupons ?

Thanks in advance,
MSF

@Nicolas,
Thank you, this works with the coupons.
The only issue I found now with the prices in the main product.

I set all priced to $3.00, the way I did it was, delete all the price, and re added them from Qty 3, 6, 12, 24 & 51
So they looked like the image below.

The only problem now is that the qty is shown only with the dropdown (select by price) of 51.

I had to go back and delete all the prices, re-enter starting 51,24,12,6 & 3, then is shows correctly.

Is there some option to turn on / off in the configuration to fix this ?

Thanks,
MSF