Sale Price v Sold Price

I am trying my hardest to make up a custom report using the price I have sold inventory for compared to what I would have normally sold it for and what it cost, but it seems hopeless.
For example, I normally buy a widget for $12 and sell it for $25, but I have a special customer that I only charge $20. I have another customer that gets charged $30.
The report can only seem to retrieve the Sales Price I have entered in the Inventory Item edit page.
I need the actual price the item was sold for on the receipt or invoice.
I used to use the General Ledger to create this in excel, but the removal of Item Names from parts of the report have made this virtually impossible.
Is this possible, and if not, will it ever be possible?

You need to work with postings to the income account, not inventory item parameters. Sales price belongs to the inventory item. Unit price belongs to the general ledger transaction stemming from the line item on the sales invoice.

Can’t find Unit price anywhere in custom reports. No guides for custom reports.
I’m getting extremely frustrated with this program lately.
Here’s what I need…

The Invoice

I need a report that gives me Code - Description - Qty - Unit price (Net or Gross) - Cost price (Net or Gross)

Here’s what I get


But that is all wrong!! Where am I going wrong?