Congrats and welcome to the forum!
Look it over for body panel alignments, any scratches etc, and also on anything in the interior. Check the brake rotors to make sure they're clean (no rust), check tire pressures (should be 29 front 32 rear). If you pick it up at the dealer, they should go over how to pair your phone, set things up on the infotainment screen with all it's preferences, etc. I'd recommend choosing the "Reset Audio" button on the screen when checking the audio preferences which seems to improve the sound system performance.
For the Homelink system, if you have a garage with an automatic door opener, when you're at your garage, hold the remote opener next to the inside rear view mirror, then press and hold at the same time both the open button on the remote and one of the 3 buttons on the mirror. You should see the light on the door opener in the garage flash twice, and that's it. Your Homelink is paired.
When setting the mirrors, their position is linked to the seat memory buttons. To set all of them together, press the M button on the door panel once, then make all your adjustments. Once you're done, then press and hold either button 1 or 2 on the door panel and you'll hear a beep. That's it. Your seat and mirror settings are now memorized. If you decide later to tweak any of those settings, like maybe the seat or a side mirror, follow the same procedure above and it will update your settings. Just as a tip, choose button 1 for your driving settings, and then move the seat all the way back and set that as memory setting 2. That makes it easier to get in and out of the car. After the settings are done, press and hold button 2 until the seat moves all the way back to get out of the car. When you get back in, press and hold button 1 until the seat stops moving forward and you're back at your driving settings.
I'm trying to think of anything the dealer might not tell you, or hasn't been generally posted in the forum, but that's about it. It's a wonderful little car; fun to be in and drive. The brakes are VERY touchy at first, whereas the clutch has a fairly long throw.
Have fun and let us know how your experience goes!