If you have the cash to spare and know you're going to get into it, start off with some better stuff than you get in a kit.
This should be standard: Get the Satern funnels for each caliber you load, a good set of calipers, bullet AND headspace comparator sets.
Optional: A tumbler, auto powder dispenser, brass prep station and trimmer.
Don't go crazy trying a bunch of powder right off the bat. Ive had best luck with Hodgdon stuff across the board. I'd stick with varget, h4350, and H1000 depending on what you're loading.