People need to learn how to undercut. They need to learn the value of the items they sell. Just tonight I realized I was the only one who still had Living Steel Belt Buckles up for sale. They were at around 550g. I took the opportunity to reset the market. I bumped them up over 1000g. Now I did this because I figured they would drop relatively quick. I didn't think they would drop this quick.
First I got undercut to an even 1000g. This is fine with me. I posed at 999g and I was sitting as the low price for a couple of hours. In that time I sold 3 Belt Buckles. Not too bad.
Then someone undercut all the way down to 650g and then another person to 550g. Now. WTF! Seriously? Come on people. Now Considering there are 3 up at 650g and 1 at 550g I am not going to buy them out to reset. I did choose to just undercut the one at 650g and hope no one else decided to undercut the cheaper one before it sells.
So end rant and begin lesson. When undercutting do so by a small amount such as 1 copper, 1 silver, or even 1 gold. This may seem like a messed up move but it is what your competitor would like you to do. Why? Cause it maintains the market price. Keeping prices up helps all those selling including you. So you undercut them, they undercut you and so on and so forth. You go back and forth 20 times and the price has only dropped 20 copper. This is a good thing. They buyers will still come, especially with an item like belt buckles. This is an item everyone needs.
No there are times where someone way way over prices. You don't want to undercut a linen cloth by 1 copper if someone is posting it at 10,000g. But you need to understand you buyers, the market and what people are willing to pay.
One thing that helps with quick posting and easy undercutting if you are new to gold making is addons. Now most gold makers love Tradeskill Master (TSM) but it has a high learning curve and can be intimidating. So another addon I suggest is Auctionator. This will add some new tabs to your AH window. Simply click on the "Sell" tab. Then drag and drop the item you wish to sell in the top half of the window (See below image for auctionator window).
Try this out. You will find that it does not matter if you undercut by 1 copper or 100g. If your auction appears on top when a buyer searches for an item, they will buy it. You will not get a faster sale by undercutting more unless you price the item so low that the mats are worth more then the item itself. If this happens another gold maker will probably scoop it up and relist it at a more profitable price.
Good luck and thanks for listening to my rant.