With a base Charisma of 7, the Hard Bargain Perk Card equipped at Rank 3, and Grape Mentats (which reduces the prices of items sold by vendors at 10%), the cost of mutation recipes comes to 17600 caps, and serums come to 3520 caps. Note that Perks and items affecting NPC prices cannot affect the prices set by players at their C.A.M.P.