Group Discount - How to NOT apply other discounts?

[jplanet]

I have a store running a sale of 10% off of all books. Teachers and Librarians get a much bigger discount, but the client does not want them to get the 10% discount in addition to their discoount...

Any suggestions on the best way to do this? maybe by using coupons somehow?

[Ajeh]

There is not an option for this built into Zen Cart at this time ...

You would need to custom code something to test for existing product discounts, specials, sales etc. prior to applying the group discounts ...

Note: if I usually got 10% off at your shop ... then found something on sale/special for 10% off and found I was no better off without the special/sale ... I'd be a tad bit miffed ...

[jplanet]

There is not an option for this built into Zen Cart at this time ...

You would need to custom code something to test for existing product discounts, specials, sales etc. prior to applying the group discounts ...

Note: if I usually got 10% off at your shop ... then found something on sale/special for 10% off and found I was no better off without the special/sale ... I'd be a tad bit miffed ...

Teachers get 25% off, Librarians 30% off -- so they will be very happy and not expect the 10% sale that everyone else gets...

Any advice on where to look for the code that applies the group discount?

[DrByte]

The module that applies group discounts is:
/includes/modules/order_total/ot_group_pricing.php

But it works based on "product prices" supplied to it by the shopping cart. "Specials" and "Sales" are already applied at this point. All the pricing functions in the /includes/functions files are based around this same concept.

What you're asking for can be done, but is not a simple case of "just change this to that" for a few lines of code, and will require studying interaction of pricing functions, significant testing, and lots of patience.

[jplanet]

The module that applies group discounts is:
/includes/modules/order_total/ot_group_pricing.php

But it works based on "product prices" supplied to it by the shopping cart. "Specials" and "Sales" are already applied at this point. All the pricing functions in the /includes/functions files are based around this same concept.

What you're asking for can be done, but is not a simple case of "just change this to that" for a few lines of code, and will require studying interaction of pricing functions, significant testing, and lots of patience.

I see what you mean...What do you think of this approach:

- Create a group with the 10% discount
- Have that be the default group that all new customers belong to...

This way when they are switched to another group, they will only get that discount, not both...?

[DrByte]

If your "10% off" is ALWAYS going to exist, AND applies to all products in your store, that's fine.

However, all your prices will show up as regular prices, with no indication that they are supposedly saving 10%, until they go to checkout. If what you're after from a visual perspective is to show that things are 10% off, then you'll lose that edge.

Why not try this:

Regular customers: shop, seeing regular price plus sale of 10%
Teachers: shop, seeing regular price plus sale of 10%, and at checkout, get an additional 16.7% off the already-discounted prices, giving them a total of 25% off regular
Librarians: shop, regularly, but get an additional 22.22% off, giving a total of 30% off regular

[jplanet]

If your "10% off" is ALWAYS going to exist, AND applies to all products in your store, that's fine.

However, all your prices will show up as regular prices, with no indication that they are supposedly saving 10%, until they go to checkout. If what you're after from a visual perspective is to show that things are 10% off, then you'll lose that edge.

Why not try this:

Regular customers: shop, seeing regular price plus sale of 10%
Teachers: shop, seeing regular price plus sale of 10%, and at checkout, get an additional 16.7% off the already-discounted prices, giving them a total of 25% off regular
Librarians: shop, regularly, but get an additional 22.22% off, giving a total of 30% off regular

You are a genius! That is perfect! How do you calculate that? It will be a very handy equation to have stickied to my monitor...

[DrByte]

A = Full Price      (ie: $90)
B = discount #1  (10%)
C = Discounted price #1  ($81.00)

D = discount #1 (25%)
E = Discounted price #2  ($67.50)  =  A*(1-D)

Discount Difference = (C-E)/C

[jplanet]

A = Full Price      (ie: $90)
B = discount #1  (10%)
C = Discounted price #1  ($81.00)

D = discount #1 (25%)
E = Discounted price #2  ($67.50)  =  A*(1-D)

Discount Difference = (C-E)/C

This is great, thank you very much for taking the time to write this!

[kotp]

I have found this thread to be very interesting. I have a different problem in my store.

I am trying to sell gift certificates (wonderful feature ) but would like anyone in the 5% club to not get a discount on the gift certificate, as this would potentially cause a double discount on a purchase. ie., Buy a gift certificate for 50 dollars, get a 5 percent discount, then purchase something with the gift certificate for $50 dollars and receive a 5 percent discount again.

Is there a way to limit the Group Discount to not be applied to a product, or am I thinking of this the wrong way?

Thanks.