Here's everything you'll need for a full-featured auction house
Let's start with the Auctionner, when you press E (default key) this window is displayed:
So here you can buy or sell your items and resources.
The stockman and the Aucion House Transporter
TheAuctionner, The stockman and The Hatchery work the same at the buy and sell level.
For all sales you will be asked for a tax of 1 Silver.