Hard-to-Find cars in Forza Horizon 4 are a selection of cars released post-launch and can only be obtained as either a reward from a Festival Playlist, a Season Event, or by purchase when they're available in the Forzathon Shop.
Cars that can only be obtained as either a Festival Playlist reward, a Season Event reward, or as an item that can be purchased from the Forzathon Shop, are labelled as "hard-to-find" within the player's Car Collection; a checklist of the player's owned cars, which can be found within the Cars section of the pause menu.
Some cars labelled as hard-to-find cars were integrated as rewards for post-launch game modes and player milestones following their inclusion, but they are still labelled as hard-to-find, but aren't as difficult to acquire as typical hard-to-find cars.
- Some hard-to-find cars were changed to be rewards for progressing through post-launch events:
- The Ferrari 812 Superfast became a Star Card: Story reward with Update 11.
- The Ford #25 RTR Mustang became an Horizon Life: Drift Adventure tier 19 reward with Update 8.
- The Ford Capri RS3100 Forza Edition became a Star Card reward with Update 12.
- The Ford F-150 Prerunner DeBerti Design Truck became an Horizon Life: The Eliminator tier 15 reward with Update 17.
- The Hoonigan Gymkhana 10 Ford Focus RS RX became an Horizon Life: Skill Streak tier 10 reward with Update 6.
- The Hot Wheels Rip Rod became a Star Card: PR Stunt reward with Update 11.
- The Morris Mini-Traveller became an Horizon Life: Express Delivery tier 8 reward with Update 20.
- The Car Collection has incorrect unlock requirements for some previously hard-to-find cars:
- The Ferrari 812 Superfast can be acquired by completing all Star Card: Story challenges.
- The Ford Capri RS3100 Forza Edition can be acquired by completing all Star Card challenges.
- The Hot Wheels Rip Rod can be acquired by completing all Star Card: PR Stunt challenges.