In the default installation of Zen Cart, it already has a "Group Pricing" feature where you can create a "group" and associate it with a store-wide percentage discount. This is done in Zen Cart admin under "Customers -> Group Pricing" ...
Here you see that "Group 10" would get a "10%" discount. You can give the group a better name, such as "wholesalers" (which is what this feature is typically used for).
You can then assign customers into that group by menu "Customers -> Customers". Select the customer and edit the customer's information
Now when this customer checks out, the group discount is applied for that customer.
One of the drawbacks is that the discounted price is not shown when the customer is logged in an browsing the catalog. The discount is shown and applied only at checkout. The discount is only by percentage. In other words, you can not set a specific discounted price. And the discount applies to everything in the store or not. You can not have it apply to selected items.
To remedy some of these issues, there are two Zen Cart mods that are popuplar: the "Group Pricing Per Item" and the "Dual Pricing - WholeSaler Pricing" mods. They are similar in concept, but different in implementation.
The "Group Pricing Per Item" is a Zen Cart mod that you can download and install from link here. It uses the Zen Cart's group pricing page and you assign customer's to your group just like before. Except that if you name your groups the same names as what is defined in the mod's file, then those groups will not use a discount percentage; instead those groups will have discount on a "per item" (or per product) basis. You can have up to four groups and the group names can be changed if you make the necessary modifications in the mods files (as explained in its instructions).
The mod will add addition prices fields to the product entry page ...
where you can enter a discounted price (not percentage) for each of your groups. If you don't enter a price for a particular group, it will show zero. But in the storefront, it will show the retail price to the customers of that group. A zero means no discount price.
With this mod, the default ZenCart group pricing by store-wide percentage still works as long as you do not name the group the same name as the group defined in the mod's files.
This mod located here does not use Zen Cart's group pricing page. Instead, it just add one extra wholesale price field in the product entry form ...
However, you can enter up to four level of pricing in this field in a hyphen-separated list as in "50.00-60.00-65.00-70.00".
To give a customer the wholesale discount, go to the customer records in "Customers -> Customers" and you see an extra field where you set the "wholesale pricing level" ...
Regular retail customers should have this set to 0 for no discount.
Both mods makes modifications to the database. You can not use the two mods together; use one or the other.
This tutorial is applicable to Zen Cart version 1.3.8.
