Leave a car at the dump to receive the corresponding power-up:
 
Car Power-up
Aniston BD4 Free Jail Card
Beamer Flame Thrower
Big Bug Machine Gun
B-Type Invulnerability
Bug Machine Gun
Dementia Invisibility
Miara Rocket Launcher
Michelli Roadster Machinegun
Minx ElectroFingers
Police Car Cop Bribe
Romero Armor
Schmidt Health
Shark Molotov Cocktails
Taxi Double Damage
U-Jerk Truck Machinegun
Z-Type Silenced Machinegun