Viewing several products on a case from multiple orders

I am very new to CRM so I apologize in advance for my lack of know how!

I am attempting to create some sort of grid within the CASE form where we can pull in the sales order, product, price.  Customers tend to call us and report issues pertaining to multiplier item numbers.  So ideally we would need the following

1. order lookup
2. product lookup (from order)
3. qty (whole number entry)
4. cost per unit lookup (from order)
5. an extended total of qty x cost per unit (calculated field)

We need as many rows of data as necessary (assumingly not to exceed 50) as some customers claim 1 part and some claim 20 parts at a time.

Something that looks kind of like this:

and so on...

I was able to create a 4 column grid with Order, Product, QTY, and price per unit via the form editor and creating new fields (as you see I need at least 5)... but in looking at the tables this info hits in SQL it is a linear string of data.  I was hoping to somehow create a new table to house the data that would hold the following:

• Case Title
• Reason Code (custom field, drop down option set- only one per claim)
• all of the items listed above 1-5

Something that looks like the above.

Any suggestions welcome, I am willing to try anything to get this to replace our current claim/case process, but it needs to be as robust as our current system that was written specifically for us.

Thank you in advance for any suggestions.

-Nicole