The Auction House is a feature where players can put their own cars up for auction for in-game credits, or bid on other players' cars.
Can you buy DLC cars in the Auction house?
Players who own the DLC for a particular car can buy and sell those DLC cars in the Auction House, but players who don't own the DLC will get an error message when trying to bid on DLC cars. All players can bid on Horizon Edition cars as well as other exclusive cars (Forzathon, Barn Finds, etc).
Why did I get less than the bid price for a car I sold on the Auction House?
Like real life, the Auction House takes a commission on sales, which increases due to price and other player paints and tuning setups applied to the car.
How is it that other sellers can set a higher Buy Out price for the same car I'm selling?
Users who have Legendary status as a painter or tuner have the benefit of higher Auction House ranges.
Why do I keep getting a Bid Failed message?
The Auction House has a limit on the number of transactions within a 24 hour period. Come back the next day and try again. In unusual cases, rebooting your equipment may clear error messages.
Where is the car I won? Where are my credits?
Make sure you complete each auctioned car by selecting it and claiming the car or your credits so they are added to your garage or account. If you are certain you have done this and apparently lost credits or cars while trying to claim them, first reboot and check again. If you still cannot access or find your car, then fill out a ticket and one of our Customer Advocates will investigate.
This video via Good Games shows the Auction House and Auctions menu:
Details: Seller, "Legend Painter," "Legend Tuner," Highest Bidder, Highest Bid, Buy Out price, Time Remaining, plus Auction Options and Auction Alerts.
(Written by Manteomax)