First off, if this is a repost I apologize. This is what I do when I have a BOE I'm looking to sell quick.
-Mail the item you're trying to sell to an alt and post it on the AH.
-Go on your main and in trade chat say WTB name of item for about 20 or 30g more than you posted
Usually someone looking to make a quick 20ish gold will buy it out and try to sell it to you. When they whisper you just say you changed your mind and pick up the gold from your alt.