If you want to differentiate tax between some of your customers, at DealPOS you can do that. So when the customer makes a purchase, the tax itself will be by what has been set in the customer contact.
Here are the steps to assign default tax to each customer:
Step 1. Select customer contact then click the customer name
Step 2. Edit the customer information
Step 3. Change default tax in Sales & Pricing then Save
So whenever you selling the tax should be follow the default contact tax that you set.
You might also like to read these articles below:
To add new customers and suppliers individually, you can check this article Add New Customer & Supplier
To add new sales person, you can check this article Add New Sales Person
To add customer and suppliers in bulk, you can check this article Import Customer / Supplier
If you want to create a customer group for multiple customers, you can check this article Create Customer Group
To add member exclusive for outlet, you can also check this article Member Exclusive for Outlet
If your customer turns out to be your supplier too, you only need to make 1 contact, you can check this article Assign Customer Contact as Supplier