The action is worth $300 if nothing else. Can't buy an ADL that cheap, can't buy a bare action that cheap, but not everyone is looking for a project gun, so a lot of fools end up selling 700's cheaper than bare action price. A shot out barrel is a detraction - spin it off. A beat up stock is a detraction - pull it off. Then the bare action will often bring more than the average Joe Blow Deer Hunter will pay.
So for me, a 700 action should at minimum be worth $300, unless it's completely wallered and loose.