I normally can set this up for glyphs but with ore/herbs it's different because they're in stacks of 20. When i try to post my ore, it says lowest buyout is 25s, your threshhold is 3g. The 25s buyout is for a stack of 12. How can i make QA ignore stacks that ARN'T 20 and only look at the prices of 20 stacks?
Unfortunatly as far as I know QA3 only allows the option to ignore stacks over a size, not under. This shouldn't be a problem really though because the higher the stack, the cheaper it should be per ore. If it's really an issue for you, download Auctionator. Once installed, simply Alt+click the ore in your bags, select the stack to undercut (the first stack of 20 by the sound of things) and press post.
QA goes by per item prices even when posting in a stack. So if you want to post auctions without going under 20g for a stack of ore or whatever. You have to set the threshhold to 1g. hope that makes sense.
^ Just set the threshold Per item in the stack. So if you want a threshold of a 20 stack of something to be 20g, set the threshold as 1g, if I'm correct.