I have a list/column of company names that are receiving product.
Within those companies, some are are forfeiting certain quantities of
the product to another one of the companies. I want to know in total
what each company is receiving.

ColB ColG ColH
Abc co. Wxy co 10
Def co. Rst co 5
Jki co. Rst co 40

The vlookup is simple enough, lookup the company name in column B and
find in column G and return the quantity in column H. The company in
column G may be receiving product from multiple companies so how do I
get the vlookup to sum the returned matches (i.e. Rst co = 45)?

Or should this be a different function? (There are many columns in
the worksheet so I cannot change to a pivot table for my purposes).