Start the game and go to bot lab. Build a robot with anything you want and can afford. If you meet the 750 weight limit and still want to add more, sell your armor and add untill you get to 750 pounds.(Or where ever you end up). Now add armor of any kind and it will let you go over 750. If a part gets blown off in battle, sell your armor, put the part back on, the buy the armor back.