With the deployment of Uprising 1.5 we will be making an important change to the in-game market with regards to Blueprint items. This means that after the Uprising 1.5 patch has been deployed, all existing Blueprint items GÇô including militia items GÇô will no longer be available via the in-game market. This will be an important step towards forging a robust in-game economy for DUST 514, and establish a solid foundation for implementing key economic features for the game in the future.

i wonder if eventually, we could spend an insane amount of aurum say about 20000-30000 to make something into a bpo, then sell copies of it and make a profit.

If anything we will just be able to buy bpo's off the player market in eve if you have an eve character.

So you think CCP is going to remove all aurum items from their market when player to player trading is introduced? I foresee people charging aurum for Officer Weapon and salvage only's.

I thought aurum wasn't exchangeable between players, due to legal issues of some sort.

Initially, you will not be able to transfer Aurum to other players. This is part of our initial security procedures rather than part of our design for this system. Once well established, you will be able to transfer Aurum to other players. You can also, or sell your Noble Exchange goods on the market for ISK.
From EVElopedia, Aurum

But honestly I have never played so I really don't know

I thought you could

Aurum can be acquired by converting PLEX into AUR, or by purchasing and converting Aurum Tokens.

AUR appears as a separate balance item in your character's in-game wallet and cannot be transferred from one character's wallet to another character, even if those characters reside on the same account.

Aurum Tokens are in-game items and as such can be moved and traded like any other in-game item. Your character can add the value of each token to your in-game wallet by right-clicking each Aurum Token and selecting "Redeem for AUR". After this step is taken the AUR is non-transferable.