To start off, you can find the game online in quite a few places for 30$ and then they give you an additional 25% off or so knocking it down to 22 or so.
Here is a pretty good video explaining what has been announced for the game release end game.
http://www.youtube.com/watch?v=bawIPQlqbK8Check out his videos, I enjoyed them.
As for rare hard to obtain items? I have no clue to be honest, I know it will not be like the FFXI of old.
For PVP, they haven't said to much about it. It will not be available on release, but said it will be the next content patch.
This game is going to be a time sink, the option to level other classes on the same toon and grab abilities from them and take them to your main class.