Forza Horizon 3 releases later this year, and this time around it's set in Australia. If you're willing to pay an extra $40, you'll also get a bunch of additional cars to drive in the land down under. Forza Horizon 3's $100 Ultimate edition comes with the Car Pass, Motorsport All-Stars Car pack, and VIP membership.
The Car Pass gets you six monthly car packs that include seven cars each--42 cars in total. The first pack releases in October, and a new one comes out each consecutive month with the last one releasing in March of next year. If you can't wait until October for new cars, the Motorsport All-Stars Car pack gives you 10 modern race cars to take for a spin from the get-go.
Lastly, the VIP membership grants you access to exclusive cars, events, and more. The five cars included are the 2016 Lamborghini Aventador LP750-4 SV, 2016 Koenigsegg Regera, 2015 Ferrari F12tdf, 2015 Ultima Evolution Coupe 1020, and 2015 Ford Falcon GT F 351. VIP members also get bonuses like double Wheelspin earnings, access to online events, and community gifts.
Source:
http://www.gamespot.com/articles/heres-whats-in-forza-horizon-3s-100-ultimate-editi/1100-6440868/