Creating Vendor and Customer Records for Rebates and Trade Promotions
In NetSuite, an entity cannot operate both as a customer and a vendor. Some features provided to a customer entity are not available to a vendor entity. Similar limitations apply to a customer entity.
When dealing with vendors as payers, the Rebates and Trade Promotions SuiteApp lets you generate a bill credit (vendor credit) or an invoice. In NetSuite, you can send invoices only to customers, not vendors. If you want to send an invoice to a vendor, you must create a customer record for them. To create a customer record, read Creating a Customer Record.
If a payee is a customer entity, you can generate a credit memo or a bill (vendor bill). Since you can send bills only to vendors, you must create a vendor record for customers. To create a vendor record, read Creating a Vendor Record.