The DKP System only goes by Character, and the guild bank functionality is not ready yet for LOTRO, but I'm working to add and hand-entering of inventory data for that in the near future.
Not sure if this helps ya or not chops but what I am doing is using a point system.. through the dkp.. and the items tab in admin to enter items <a place to and the quantity would help> and ppl can then request item button..