They are highlighted by an icon of a billboard. Nearby billboards will be telegraphed to the player and records its location on the player's map.
Driving through a billboard will count it as being collected, and will be added to the player's journal as being found as well as having a tick next to its icon on the map.
Each billboard collected rewards the player with 6,299 and 31,499. Collecting all 30 will unlock the "Does Not Obey" award.
There are a total of 30 billboards across Fortune Valley; 10 in Mount Providence, 6 in Liberty Desert, 3 in Silver Rock, and 11 in Silver Canyon.