Various Cheats:
Create a new player name using the following names:

SheBeast - Get She beast car

Brain - Get Brain car

MOISDNE - Get money & cars

Reptomicus - Get Repto Car

Invader - Get Invader Car

Best Car:
Go to sumpter town and talk to the boss at the station and then go outside and press T and then Trixie and that will get you the Hot Rod.