In terms of hardware, what are some good cost effective resources and what what things might I want to consider differently than what I am used to in both the Mac and Windows worlds? I need smart home management, a plex hub, and photo editing, as well as the usual other stuff.
EDIT: I use Capture One for photo organizing and editing. I have old computers I can repurpose for this endeavor, but they are pretty old. My main thought for this post was looking into what kind of hardware I could consider for building a new Linux system from scratch. I am very much am inclined to switch to Home Assistant,because Siri is dumb as a bag of rocks, and AppleHome does not have the features I want and is extremely buggy. Everything I have currently is in the Apple ecosystem, and my daily driver is an M2 Mac Mini. I am not inclined to put Linux on the Mac Mini at this stage. I use the complete Proton suite for all that stuff. Thanks!
The most cost effective solution is the hardware you already own. Chances are good that everything will just work. You can boot almost every Linux installation medium directly from the USB stick into a functional desktop and try if you can access the internet and have working sound.
Lacking that used Thinkpads are usually great. Try to stay away from nVidia. NVidia drivers aren't bad but they are much much worse than AMD and Intel's.
Isn't smart home stuff done over the browser? Plex should work but you might consider switching to Jellyfin. For photo editing take a look at Krita and GIMP. For office stuff you would use Libre Office.
Almost all the programs you would use on Linux should be available on Windows and Mac as well, so you can try them out now. Chances are, if it is open source it should run on every OS.