Hi natewallis,
Thanks for reaching out. It sounds like you are looking to create Employee's which will be used as the Salesperson for your invoices. Here is the link to the Employee Endpoint documentation to do this via the API.
If you are looking to create inventory items via the API, please refer to our Inventory documentation.
Please feel free to contact us at developers@myob.com if you have any further queries.
Thanks,
Jacob
MYOB API Team
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