It’s incredible, what people would buy from AH.
One of my former guildies sold a lot of skinning knifes for more than he gave for it at the vendor. Why would people buy such a thing?
I have no idea.
But I do know a WoW gold trick, where you easily can buy a thing for silver and sell it again for gold.
Make it a habit to check every vendor, you meet. Sometimes, it’s a man walking on the road. Other times, they are placed inside huts or shops.
Look out for rare things from the vendors. You’ll see a number between brackets beside the item, like this (1). This means that only one is available for a periode of time, for everybody, not just for you.
Use the Auctioneer plugin to see, if the item has any value in AH.
But beware – sometimes this trick only works a few times, and then people find where to buy it themselves or wait for the prices to go down in AH. Some of the items on I tried it with used to be sold for 80 G on our server. Now it’s down to 30 G. Still easy gold, though.