Automatically adding shipping charges to an invoice

Is there a way to automatically add the shipping charge to an invoice? The charge will always be the same.
How can that charge be automatically calculated and added to the final cost?
Thanks!
--Dhara

Shipping has to be chosen once the order has been created. This is because many AllProWebTools users use real shipping rates that depend on the weight of the items entered, and the address of the customer.

However, you can still set a flat rate for shipping that you can use as a shipping option. If you go to Store->Shipping Manager, then select the shipping method you will be using, you can set it to Calculate by a "Flat Base Rate."

Please let me know if you need any more help setting up your shipping!