If your account has Legendary cars,

1. Please list any legendary cars and make the "buyout price" at 20M at the auction house till to reach your order's amount.

2. Please set the "auction length" as 24 hours.

If your account has less than 1M FH5 credits or no Legendary cars,

Please sell anything you have at the auction house, tell us at Live Chat (In the right bottom of the page).

Our gamer will buy these cars then you have the credits to buy legendary cars at the auction house. (Please see the instructions below for how to buy a legendary car!)

https://www.u4gm.com/news/forza-horizon-5/how-to-buy-legendary-cars-at-the-auction-house-for-sale