The cost, as said above, is not fixed but a product of the list itself (if your interested in more details we're sure to be happy to bore you with them

). For your purposes, I'd take the Codex list, subtract 25 points from the formation and then divide by the number of units. Good enough to goverenment work, as they say. Provided you follow the same with all sides, you'll have a relatively equal starting point for friendly play. After some games you all may find that you want to increase / decrease points.
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