Building relationships in data model to leverage power pivot - circumventing unique key ID issue

Thank you for the response, I'll look into learning some DAX and virtual relationships.

I'm find with that formula, it's aggregating the aggregate ($7,500 * 5 = $35,000) instead of providing the COGS per service Line per Product ID (as you have shown above under COGSv).  I couldn't find TREATAS so used INTERSECT.   

I tried creating another formula, which also produces the same result.  Is there a formula (other than TREATAS since I can't seem to find/ use it) which can summarize COGS per Product ID and Service Line (rather than summing COGS per Product ID, and applying that to each Service Line row, and then aggregating that - which is what is currently being done).  

This is my current formula:

=CALCULATE(

SUM(COGS[COGS]),

INTERSECT(

SELECTCOLUMNS(

SalesTable,"Criteria1",SalesTable[Service Line],"Criteria2",SalesTable[ProductID]

),

SELECTCOLUMNS(

COGSTable,"Criteria1",COGSTable[Service Line],"Criteria2",COGSTable[ProductID]

)

)

)