This question came up in my game, via email, and I figured I'd write the answer down for all to see.
How long does it take to get something enchanted
Up to 100 points, it can be done in a single day.
Above that, it's Slow & Sure Enchantment.
Per GURPS Magic, Slow & Sure is 1 point of energy per wizard per day.
Also, I assume a skill-20 master enchanter, with 5 assistants. This brings the skill of the item down to 15, for a Power 15 item. Only one circle can enchant an item at a time.
To make it simple, they don't take days off.
So for example, Lighten on a full suit of armor costs 500 points (and $10,000.) It takes a circle of 6 wizards 500/6 = 83.33 or 84 days to enchant the item. During that time, they need full unfettered access to it.
Technically, you could swipe it and return it within 15 hours, but anything that messes it up will mess up the enchantment, and you have to pay in advance, so that's a terrible idea.
In any case, I run 1 real day = 1 game day, so according to this site if that was ordered this Sunday (9/29), it would be done 12/22. Ho Ho Ho, Merry Christmas!
I want a rush job!
There is a way to get it done faster.
Talk to Black Jans, the Wizard of the Northern Marches, Master of the Black Hand, First Enchanter of Cashamash, etc., etc. He's the strange wizard whose tower just appeared in a previously empty part of Stericksburg just before Session 18, down an alley that used to be a dead end. His tower is sometimes in Stericksburg, and sometimes is mysteriously gone from the city.
If he's around, and he's willing to do it (reaction roll, every time), he'll enchant any item you want in one week, for double cost.
That Lighten spell? One good reaction roll (bribes, gifts, and not being a social misanthrope all might help), double cost ($20,000), and one week. And done.
So why would anyone use the slow method?
Double cost is still double cost.
And Black Jans's tower isn't always there.
And he doesn't always agree to do things. Well, technically, no one has met him, only his mysterious servant(s), the Kio. It, or they (it depends) are the ones who deal on his behalf.
Out of game, he's a great deal, and he's there to expedite the whole process, let me occasionally give people quick enchantment, and otherwise keep things moving. Also, it's a tempting money drain. The enchanters are cheaper and slower, and a good idea if you've got an item you want done and have a spare one/spare set to use in the meantime. It's get some good rolls and pay a lot, or just pay the going rate and get it for sure . . . later.
And that's how I'm doing it.
(And I've noticed that Total Party Teleport I and II were extremely pivotal sessions in my game. Many things were discovered, many things happened, and many events started to roll from there. All because Nakar bullied everyone into a "shortcut" that he clearly didn't fully understand how to use . . . )