Hi i am trying to customize the Bonus buy can any body tell me the steps inclusing the VBK1 maintanence
You use this function to create conditions that only apply when the prerequisites and requirements specified in the scope of functionality and defined by you are met.
The following Customizing settings must be available:
A field catalog must exist.
Condition tables must be defined.
An access sequence for the condition tables must be defined.
Condition types must be defined.
The Customizing settings for bonus buys are contained in the Sales section of the IMG under Basic Functions.
Scope of Functions
You can determine the type of discount granted as a condition. The following types of discount are possible:
 Fixed price
 Fixed discount
 Percentage discount
 Free Goods
You can define quantity-based or value-based scales.
You can also determine whether the discount is granted only once or more than once per sale.
You can define the articles for which the system is to grant the condition. To do so, you specify one of the following as the target of the bonus buy:
 a single article
 articles belonging to a specific grouping
 all prerequisites
 all articles purchased together (the whole transaction)
You can define which requirements are necessary for a bonus buy to be granted.
Requirements refer to the total sale in general (for example, a minimum sale) or to other aspects of the sale (such as the use of a credit card).
You can determine the type of bonus buy granted. You thus determine how the system should logically link the individual prerequisites. A distinction is made in the system between the following types of bonus buy:
At least one of the prerequisites defined for the bonus buy has to be met. The following examples illustrate how multi-deals are typically used:
CDs on a particular rack cost 5 $ each, but you offer any three for 10 $.
When a customer buys three CDs that are on special or one particular CD, you take 10 % off the price of any compact disc player.
 Combination deal
All the prerequisites defined for the bonus buy have to be met. The following example illustrates how a combination deal is typically used:
When a customer buys a pair of skis and a pair of boots, you give them a free pair of sunglasses.
You can define the individual prerequisites that have to be met for the system to grant the conditions. These items have to be involved in the transaction (the customer has to buy other articles, for example, or hand over a coupon).
The articles involved can be single articles or articles belonging to a grouping you previously defined. You can enter a quantity for each line. This defines how many of the articles have to be in the sale for the condition to be granted.
If you define 2 as the quantity of a particular article in a grouping and you include the grouping in the prerequisites with a quantity of 3, a customer has to buy six of the articles before the bonus buy condition is granted.
You can specify that a bonus buy is granted if the customer buys a specific quantity previously defined as a prerequisite.
You offer a special price for customers buying particular drinks in crates of six. The bonus buy will be granted if a customer buys a crate containing two bottles of drink A and four of drink B.
To map this to the system, you would create an article grouping containing drink A and B, each with a quantity of 1. You then define a bonus buy condition with the article grouping as a prerequisite. You enter a quantity of 6. You also select the summation indicator
Bonus buy conditions can be reached from the initial screen of Retailing by choosing Master data--> Condition/Arrangement
> Conditions: Sales> Bonus buy--> Bonus buy -->Create.
When you save a bonus buy condition that uses an article grouping, the system determines the articles currently contained in the grouping. The system does not take subsequent changes into account, for example if you remove an article from a promotion contained in an article grouping or delete an article grouping.
When you create a bonus buy condition that uses an article grouping as part of the prerequisites, an entry is created in the access table for condition records for every article in the grouping. Therefore, you should try to avoid having whole merchandise categories, for example, in an article grouping.