Recruit-a-Friend Doing My Homework

Ok, this weekend I am planning on setting up my first duel-box setup with 2 accounts for the purpose of lvling characters with the LFD tool while controlling both a tank and a healer.

In order to do this I am planning on first using 2 x 10 day trials to get a feel for the layout and make sure my mods and key-binds are all set up and working.

First Set of Questions (10 day trial):
- IIRC the 10 day trial account prevents you from lvling past 20. Is this correct?

- Will I be able to move Items via mail or trade from my Main Account to these trial accounts ( Bags, Gold, Pots, Weapons )?

- If no, are 10 day trial accounts able to utilize the AH in any way?

Second Set of Questions ( Recruit-a-Friend ):

- This starts off as a 10 day free trial in which the character on the trial account can not lvl past 20 correct? Same exact rules as above?

- In the RaF Legend it lists "Friend upgraded to a standard account" does this simply mean preBC box? Or will it have to be upgraded to Wrath?

Third Question ( Authenticator ):
- Do I need a different Authenticator for each account? Or can I use the same one for multiple?