I know this guy that is selling his wow account for $75 and I'm really interested since he has a full wrathful Pally/Warrior with 25k gold. He is selling it so he can pay his car bill. So I guess what I'm asking is if it's still possible for him to get his account back even though he gives my all the info and I add a authenticator?
It is. He can just use his ID to retrieve account. Just ask for photocopy of ID then it will be a bit harder for him (but I don't think he would give you one for 75$)
After a few months he will get bored and recall the wow account. This is how usually works(even for 200$+ accounts)