Just some rough math says if you could sell it, you have sbout $800-$900 of stuff used.
Still, you are not 100% whole in terms of a process. So, what do you want to load first? I would start with the RS5 kit. Does it have a powder measure?
How good is this friend? Do you trust the gunpowder? To me, it is wired to have two cans of canister grade powder open...can he tell you why?
The tarnished, but primed 357 is ok, if you know the primer and it is uncontaminated. Primers are usually good, I think in a bag.
Also, in assuming it is all in good to go condition, is it?
I would start by picking a caliber and reading a manual of the process to get started. The ABC's is ok, but maybe a book like the Lyman manual would be better.