Getting Started
Create Item Invoice
    A summary of the activity
    Creating item invoice
    Attaching Notes
    Modifying taxes, charges or discount details (valid)
    Modifying payment schedule
    Viewing account posting information
    Modifying part invoice details
    Viewing invoice summary
Create Expense Invoice
Edit Item Invoice
Edit Expense Invoice
Authorize Invoice
Hold / Release Invoice
Reverse Invoice
View Invoice
Setting function default
Viewing function defaults