Some good resources to really understand what to look for in a high quality shotgun for clay sports.

Hello all - trying to wrap my head around what the real differences are between a $4/6k shotgun vs a $15/20k shotgun. Is a lot of it branding and reputation, or can some of it be really based on design, quality of materials, etc.? I’ve done a lot of searching, but can’t find solid sources that say things like, “here are what separates low cost barrels from high cost barrels”, “here are three types of trigger designs you should look for”, “here are the 6(?) most important things to look for/evaluate”. For example, when it comes to cars, computers, cameras, 3D printers, etc., etc., I can spend a lot of time learning about all the critical components so that I can say with some confidence, “yeah, this one is definitely worth it”, but for shotguns, I’m just not there yet. So perhaps there are a couple of key books, key individuals, key web sites/YouTube, etc., that I can focus on, if so, does anyone know what these definitive resources are, as I’m totally hooked on clay sports, now just want to make a wise …and informed investment. Thanks in advance.