With this you will be able to set the cost of a product and its mark up . Will work whatever you change (price, cost , gross price)

the original contrib does NOT store the cost so I combined adding the cost from contib http://addons.oscommerce.com/info/1594 with showing the margin from this one .

I replaced sales margin with mark up because I think its better for a shop owner to know his mark up.

Iam not a coder so any clean up will be appreciated .

Please back up database and the files changed . I have not tested it on a live shop

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