The problem with the trailers has nothing to do with National Liquidators. The banks typically have a lien on the boats, not the engines, drives, nor trailer. Nat Liq cannot sell the trailer because neither they, nor their customers (banks), have title to it.
I have been successful in asking them to contact the origianl owner of the trailer and making an offer.
FYI, the current bid is way over the starting bid of $22K.