How to add Customer Group On Grandse Pos Billing Software?

Customer Groups: The percentage in the customer groups are the addition/subtraction in the product price for that group. If you have set 10 percentage for customer group, then each customer of the group will have (10%) higher price automatically calculated on sales. If you set it to -10 percent, then the products price will be (10%) lower than normal price.

When You add Customer Details You can Select Customer Group then every time of billing the discount automatically detected.