Invoicing is very useful as every time you create an Invoice, you also create a sales record in the database that you can view, and you automatically control your Stock usage. You can do three things in one go! You save an invoice, edit and delete a created invoice. When you edit or delete an Invoice, it will also edit or delete the income record in your database, and it will also adjust your Stock amount automatically.
In your Invoice creation page, a drop down list box inside a data table displays all the Stock Item in your database. If you select any of the items, and you create (save) the invoice, it will automatically reduce the quantity of your Stock Item in your database.