Im just wondering if there are any perks that add to the number of charges on magic items AFTER they are crafted. The reason I ask is that I have some merchant items that are good but have a low charge count. Do any of the enchanting perks or the like add extra charges to items you already have enchanted?

Cheers.

Do you mean can you re-enchant stuff that's already been enchanted? No, you can't remove/ modify enchantments once they're on. All you can do is get the smithing perk that allows you to improve the quality of the piece.

No I mean like staves/staffs with a mage. Mages with a high skill in desruction (Eg fire) get more charges out of a staff of fireballs than it has as standard. That idea but with a sword/bow etc. Like if I have a sword thats got 500 charges, can I perk enchant or a magic skill and have the charge count increased.

You can reduce the soul cost per activation by using cost reduction equipment. For example, if you have 100% fortify destruction equipment, your fire sword have unlimited charges.

Source: http://www.uesp.net/wiki/Skyrim:Enchanting_Effects

Ah I see, thanks for the info. Just to clarify, a high level in the corresponding school also adds charges? So If I have 100 destruction perk for fire, and say 80% reduction I would get a shedload of charges for a flame sword over and above just the reduction gear on its own?

Only destruction skill level and cost reduction equipment reduces soul usage. Mastery perks do not for some reason.

Ok got it, thanks buddy.