I think there should be a Car Rent feature in the game of every car thats already in and for cars that were in the past Festival playlists, you should be able to choose if you want to test it on free roam for a certain time limit or on an event of players choosing. Forza Motorsport 7 had it, and I think it would fit the whole open world thing of the FH5 better as well. Also it would help players make decisions if they want the car or not, and if its worth spending time to get it.