I don’t see anything wrong with starting on a Dillon. I started on a progressive, as well as many friends.I've reloaded many years. have had dillons but I don't think that's the right press for a beginner. I think you need to learn the process, make mistakes etc. You need to know the feel of a primer that's right & one that's wrong. I am not knocking the dillon, it's a great press and really spits out loaded ammo. But YOU need to be at a higher skill level so you don't have hundreds of mistakes versus just a few.
as far as brass goes, just pick it up when ever you go shooting, and offer to pick others up if you can keep it. I’ve gotten a lot that way. Bullets, RMR for 9mm and other pistol, and Hornady bulk picks for 223. Powder isn’t bad. Just check every other day online. Primers aren’t too bad if you aren’t brand specific online. Just be diligent and you can grab them over a week or two. For primers you can average 45 per K shipped if you snag 5-15k at a time. Just don’t be scared to buy 1k at a time and suck up the hazmat fee. Really you’re only increasing your reloading CPR maybe 4 cents paying $75 for shipping and haz on 1k primers, which isn’t that bad considering.