FINSYNC helps you manage payments you request from your customers. You can designate your primary customer and also additional contacts associated with that customer.
Adding new customers and contacts is easy, please follow the steps outlined below:
1. Select Payments from the top menu.
2. Select Customers from the the menu on the left.
3. To add a new contact to an existing customer record, click the customer you want to make changes to or use the search box to locate the specific customer.
Click on the Contacts tab in the top menu and then click New Contact on the top right. 
4. Enter the additional contact information for the new user and click Add Contact to save your changes.
5. Now you will see both contacts listed under the customer. The yellow star on the left of the name marks who the primary contact is for this company/customer. You can edit who the primary contact is by clicking the edit icon on the far right side.
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How to Create and Send an Invoice