I learned that messed up hatch wiring can not only knock out your 3rd brake light and make your hatch open light turn on (and off when you hit the brakes), it can also knock out all you parking lights over a year after the initial problem.
Took my car in to a dealer cause all my parking lights were out from a blown fuse (and it'd blow fuses all the way from 7.5A to 20A). Turns out that my problem with the hatch open light and 3rd brake light that I had over a year was causing a short to the rear parking lights and license plate lights. Since they're all on the same fuse, the front parking lights also got knocked out. They fixed the wiring, parking lights work fine now and the 3rd brake works for the first time in over a year as well as the hatch open light now actually comes on when the hatch is open.
I also learned that despite the high prices, dealerships aren't always total dicks. I was told there'd be a $150 diagnosis fee. That's already expensive but they didn't charge me a cent more than the diagnosis fee. I also learned that if you ask for a full synthetic oil change, they'll charge you nearly $70 but if you bring in your own oil, they'll charge you $10, filter and all. I'd do it myself if but it's against my apartment complex's rules.