GURPS Powers and Enchanting

[scc]

So if using Powers, Magic as Powers, Chi Powers, Psi Powers or pretty much anything else Powers based, what do people think would be needed for people to enchant or perform an equivalent task for their Power Source? I'm thinking that one or more Afflictions would be a minimum necessary, but additional skills or techniques or instructional books are likely needed for item made.

I'm not asking just for PC manufacture here, if the PCs need to buy an item in such a setting figuring out these basics is needed to know how hard it is to find someone to perform the task, and if the PCs need to perform a task like lifting a curse that's been somewhere for a while, knowing this gives me an idea for what they'll need to lift said curse.