Is there a tutorial for buyers on how to send an invoice for multiple items?

[asgoodasitgets13]

If we make the most money from buyers purchasing more than one item why does it seem so difficult to send an invoice after they purchase?  Only when there is an ended auction or they accept an offer can they combine the orders to ask for an invoice?  Ok loaded questions.  I am struggling with even trying to get 3 items to go on one invoice so I can tell the buyer how much she needs to pay in shipping.  This is frustrating to say the least.  Any easy hacks or workarounds or what am I missing?  The buyers don't seem to know what to do and I am sadly new to selling and I want to help them. 

[asgoodasitgets13]

I forgot to mention, I think it is ridiculous they have to be refunded.  This seems like an easy fix but maybe I am missing something.  

[lady_madonna]

@asgoodasitgets13 

The buyer places the items in their shopping cart.

If a buyer is purchasing multiple items from you, and they haven't already benefited from a shipping discount, they can select Request total from seller in their shopping cart. You can then send them an invoice with the new combined costs if you have combined invoices enabled on your account.

Here's how to check:

1. On the Shipping Preferences page, select Edit beside Allow combined payments and shipping.
2. Choose the time period during which you're willing to combine payment for purchased items and select Save.

You can then issue a combined invoice to your buyer. To do this from My eBay:

1. Go to the Sold section.
2. Select the items you want to combine into a single invoice.
3. Add the new shipping charge.
4. From the Actions menu, select Send Invoice.

To issue a combined invoice from Seller Hub:

1. Go to Orders
2. Check the box beside any orders that need to be combined.
3. Select Send Invoice for any of the orders selected.

Here is the link to the full help page regarding offering combined shipping:

https://www.ebay.com/help/selling/shipping-items/shipping-rates/offering-combined-shipping?id=4169