Buy 2 Super packs. Sell all its contents.(Except the Laser,EMP,Mini-Gun,Grenade Launcher, Heat-Seeking Missiles and the Nuclear Battery.) You should have over 4000 creds. Buy a Large Chassi, Large Tower, Large Engine Deluxe, 6 Large Wheels, Alkaline Battery, Razor Discs, Armour Regenerator, Kamikaze Bomb, Flash Bombs, Spear Gun, Rolling Pin and everything else that's good. You should have the best robot ever. You'll get to +++++ in no time.
PS Sell your other stuff also (Chassi ex)