That really depends a alot of things. My 30-06 brass usually last 5-6 reloadings before I anneal the necks. That is the process of taking a torch and heating the neck of the brass to make it pliable again. I only do this to plinking ammo, because I, myself, do not fully trust the method and it is alot easier to end a day at the range than it is a hunt because fo ammo problems. Honestly, only you can be the judge of that. I am very picky when it come to target/hunting brass. I weigh them all and ream the primer pockets so they are perfect. You have to visually check for split cases, deformed brass, etc. to come up with a reliable answer to how long brass lasts. For instance, I cannot reload brass shot out of my H&K 91 because of the fluted chamber. Similarly, I cannot reload some of the brass from my Bushmaster M4 because of the way it hits the brass deflector.
When it comes to nickel and brass, nickel does not last as long reloading. I have found that after only a few reloadings, the nickel plating starts to flake off.....but, you can still reload it (Not after the nickel flakes off, of course). The reason manufacturers nickel plate them in the first place is because they feed smoother because of the nickel. I do have some Coated Barnes X Bullets that I have reloaded in Winchester Nickel brass that look great, but act the same as the same load in a brass case.
There are many, many variables in reloading. I found it easier to learn from someone showing me than reading. Like you have staed above, there are just some things you have no idea what they are and do, so reding about them dosen't help a whole lot.
When you buy equipment, I highly, highly suggest the RCBS Rockchucker Supreme reloding kit. Mine even came with a hand priming tool and a priming arm for the press. The press is cast iron, and you will never wear it out or hurt it. I think I found mine for $380 at Wal-Mart about 3-4 years ago. After that, you will need dies, bullets, powder, brass (used or virgin), a case trimmer, a micrometer, and that will get you started. After that a brass tumbler is helpful. Oh yeah, and manuals for any brand of bullets you buy to reload. Barnes is the most expensive I own at $32, The Hornady is a two volume set and is a great guide, and Nosler was pretty cheap, etc., etc. Bullets range from anywhere at about $13 for 100 Hornady V-Max .224" to about $30 for 50 Barnes Triple shocks/X-bullets. Nosler Ballistic tips are fairly cheap. Powder is about $18 a pound for IMR 4064, and it will reload a couple of hundred of my .220 swift cases. primers are really cheap. Anyway, hope that helps.
SAWgunner