Associations support invoicing their market and vendor members. To do so, click on Your Associations from your account page:
Next, click on Invoices
Make sure at least one payment method is enabled, for example, having your members pay by check:
To create an invoice, click on Add Invoice and fill out the form, the To will automatically start to populate as you start typing the recipients Vendor or Market name
To notify the recipient immediately, click on Save + Send otherwise clicking on Save Only will just create the invoice and leave it up to you when to notify them.