But that means I need to maintain them for probably 5 years, and I have NO idea what ski maintenance even is. I'm trying to determine how much I should learn to maintain skis myself or if I should just drop them off at the shop every year. I don't relish learning another hobby "job", but I work on my own bikes, etc. so I should probably learn to work on skis.
Well, this is quite the rabbit hole you're peering down!
First step, look at the video via the links that Phil put up earlier.
Next, poke around the following site for Tognar Toolworks:
https://www.tognar.com
As others have said, there's some initial investment. If you keep your wish list short for now, and use some creativity, you can keep the cost down. Your local shop will have at least some of the items you'll want, but the selection may be limited and the prices may be high. For every ski tuning thing you could ever possibly imagine, visit the Tognar site.
Tognar's Web site also has a big set of instructional articles.
Your first issue, and maybe the most difficult, is how to hold your skis steady and strongly while you're working on them. The best solution is to get a set of ski vises that you can attach to a work bench. That assumes you have a work bench. If you want to spend more money, you can get a folding ski tuning table. Otherwise, you may be able to get away with using a standard carpenter's vise, if you have a home shop. Otherwise, you can get your children to hold the ski steady while you're working, and then drip molten wax on their hands and probably slip with the file, as well. Yeah, not the best plan.
The first task you want to learn, because it's the one you'll need to do most often, is hot waxing. For this, the most expensive item needed is a waxing iron. You may be able to get away with using a small travel iron. A steam iron isn't good, because the wax will get into the holes in the base. After that, it's pretty straightforward. You need some wax. To start, an all-temperature wax or one formulated for snow at about the freezing point will be fine. You need a plastic scraper. To get fancy, a brush is good to have. This is to expose the structure on the ski base.
Getting slightly more complex, the next task is sharpening edges. To start with, you might want to only get a small diamond stone. You can use this to remove burrs between sharpenings. This is important, and something you should do promptly any time you hit a rock. A full sharpening usually isn't needed more often than every few weeks, and you might choose to leave that to a shop. If you want to do it yourself, there are many types of files, file guides, and stones available.
For most people, the most complex do-it-yourself task they'll tackle will be base repairs. First, you need a metal scraper. This is to remove any ptex that has been raised above the surface, and to flatten the base after you do base welds. You can also
carefully use a small sharp knife to cut off any projecting bits of ptex. To fill gouges, you need ptex material and a way to melt it into the gouges. There are various methods. I recommend using the ptex string and a small soldering pen with a beveled flat end. If a gouge is all the way through the ptex exposing the laminate underneath, you'll need "metal string," because regular ptex won't adhere to metal. The metal string goes in as the deepest layer of repair material, followed by regular ptex on top. If you have only modest damage to a ski base, it's much cheaper and not too hard to make a repair without getting a full base grind at a shop. Every time you get a base grind, you shorten the life of your skis, because the ptex is only so thick.
I hope this gives you a start.