To customize the Payment Terms you would like to offer your Buyers, go to your Order Settings.
Under the "Payment Terms" section, you can add new options or modify existing options that will appear for your Buyers in a dropdown menu on the Order Form.
Customize Visibility of Terms
Unfortunately it is not possible to customize which options are available to specific Buyers.
For example, if you only want Net30 terms to be available for Buyers you approve, it is not possible to hide it for others. We recommend simply adding text to the option to clarify (e.g. "Net30 (approval required)".
If this is a feature you would like to see added, please contact Support.