All purchases add cash (you'll be able to buy all upgrades after the first level), unlimited rockets (once you buy them) and nitro. Note : there are 3 takes for each level, once you're done click End Take.
Stunt Crazy Hacked
Earn all the film reels on each level as you perform Crazy Stunts on each level.
Collect as much money as you can and use it to buy upgrades for your vehicle as you go Stunt Crazy.