On the subject of gold, I always liked this story (not mine):
Why do magic items cost gold to create?
Because gold is magic. The first day I was an apprentice, I remember my Maestro asked me the simple question, "why can't we create gold?" I thought it was an odd question, but as he left me alone to think about it, I realized I'd heard of wizards creating fire, summoning water, producing force, and all other of objects and effects… but never of a Wizard just sitting in a tower summoning mounds of gold. You'd think if it was possible, someone would've done it by now right? So? Why haven't they?
It’s because gold is magic. Well, a physical manifestation and metaphysical conduit at the same time, but for your purposes it is magic. When you sit and look at the evidence laid out, how couldn't you come to this conclusion sooner? Let's take dragons, for an example. When you imagine a big bad dragon, the next thing you imagine is it guarding its hoard. Hoard of what? That's right: GOLD. Isn't it odd that an entity whose literal being is infused with magic just happens to have not only an insatiable, but uncanny magnetism towards large quantities of gold, along with the urge to acquire as much as possible? Possibly the "like-begets-like" principle, hmmm?
Let's look at Dwarfs next. Their history lies below ground, closest in proximity to the veins and shafts where gold accumulates and grows (yes, "grows"). They're the only race with an inborn resistance to magic. Isn't that curious? Almost as if there's a subtle inoculation against it by such proximity for generations...
Lastly, to get back to what exactly I am doing with all this gold when I'm making your lovely magic item, or all my scrolls. You're right that I'm not spending thousands of coins upon jewels and masterwork items to hold the magic in place. That's ludicrous, but if eldritch manipulators are spending money on high end items to imbue, it's probably a personal focusing preference. For myself, as you can see, I am working with normal mundane items. Technically I am transmogrifying via prestidigitation these elegant golden coins into their more metaphysically soluble powder form because essence diffusion is easier by an order of magnitude when working with particulates instead of a boatload of walletweights. With a certain amount of forceful application of will and choice incantations, you will notice the gold powder I am sprinkling and kneading on top of the object is absorbed by said object. Remember what I said about manifestation and conduit? So the gold is not only priming these boots to be receptive towards my spells, but it establishs a channel to arcane ley lines it order to keep the magic going. Yes, it is indeed very time consuming rubbing gold powder into an item one pinch at a time while maintaining the proper mental focus. There's a reason it takes us about eight hours for every thousand gold a magic item requires. You think a consortium of magic users got together and decided on union hours for magic making? Hell no. Its plain old, tedious work, but important work if you want it to function correctly.
Now, master-of-arms and all things armly, would you kindly let me focus on the task at hand so that when I'm done, we don’t have to worry about our Holy Dictator suffering from extreme vomiting and nausea whenever he puts his shoes on because I had to split my attention trying to condense decades of intense arcane study into an elementary discourse?