Given that items are enchanted via alters in Oblivion, it`s never made sense to me that you have to pay money to do it. Who are you paying? Do you need to put coins into a slot in the alter to activate it? The use of alter-free enchanting and spellmaking mods makes it even more non-sensical. For this reason, I`ve long been searching for a mod that removes the monetary cost of Enchanting. Is there such a mod, and if not, how difficult would it be to make one?
http://www.gamesas.com/index.php?/topic/1138371-relz-enhanced-economy/ has a few ini settings related to this (from its ini):
; Those settings control the cost for various services. If set to 0, EE will not control it, so default (or value set by other mods) will be used instead.; Cost of spellmaking, where the value is gold cost per magica cost of spell.; 3 is vanilla value, 6 will make spell cost twice as much to create.set tnoEE.spellMakeCostMult to 0; Cost of creating weapon enchantments.;10 is standard value, 20 will make weapon enchanting cost twice as much.set tnoEE.enchantWeaponCostMult to 0; Control cost of creating static enchantments.;1 standard value and 2 will make static enchanting cost twice as much.set tnoEE.enchantStaticCostMult to 0
As you see, you cannot set either to 0 (as Enhanced Economy treats 0 as "don't change it"), but you can set them to 0.01 or something similar, which will make the cost only a coin or two.