We use both data contained in your invoice database and data from other related databases to generate an invoice document. Here are the values (both required and optional) used by Invoices.

Number property type. It’s used as the invoice number.Number , Formula and Rollup property types. It’s used as the total amount of the invoice.Number , Formula and Rollup property types. It’s used as the subtotal amount of the invoice. When Subtotal is different from Total, an additional row is displayed with the corresponding tax rate.Date property type. It’s used as the invoice issue date.Date property type. It’s used as the invoice due date.Select property type. When used it shows the status of the invoice and lets you filter by status in the list.Relation property type. The data from this related database is used to show Client billing information.Relation property type. The data from this related database is used to show your company billing information.Relation property type. The data from this related database is used to show the billable items of the invoice.The invoice database uses related databases to show additional information. When you press on any of the related values you will see a list with all the related databases inside your base.
If your list is empty, make sure that:
Invoices
Invoice database