I haven't seen it mentioned, so let me say: Outerwear.
Especially if you are into snow sports, the difference between quality outerwear and cheap garbage is not just getting wet sooner. It could very well save your life if you're wearing something that will keep you dry while maintaining breathability. And nothing beats lifetime no questions asked warranty where you just hand it in and it gets repaired for you. In the long term this saves a decent penny whil also reducing your environmental impact
Same goes for base and mid layers. Cotton will kill you, and lots of cheap synthetics don't breathe well. Spend money or higher end synthetics or merino.
Lastly, don't get cheap goggles from Amazon or eBay. Heck, don't get the cheapest models from even more reputable brands. You will want your goggle lenses to provide good UVA and UVB protection, while also providing contrast enhancing features like polarization and very importantly: fog resistance. You will not have a good time if you can't see where you're going. I can't stress enough how big of a difference visibility makes for your enjoyment and safety.