I am not sure if this has been suggested, but I think there should
be a tab in the auction of the pokemon holding items, it is kind of
hard to find pokemon holding items unless it is in the Promoted
auctions section :P. Sometimes 'unique' items get pass when no one
even notices, besides the price of the pokemon.
The idea of being able to see or search for items in the Auction
House has been suggested before. Perhaps this thread incorporates the idea of it being visible
and being able to search for it into one post? It was the earliest
I could find at least suggesting an idea like this.