Last year we were a little bit more than 30 lbs overweight

. The guys at the weighing station said that in all their years they have never seen anyone so horribly overweight

. Needless to say, we spent the next day and a half tearing everything we possibly could off of our robot.
In an effort to thwart the repetition of past events, we would like to find a way to weigh our robot as we go along. I was personally looking into buying a scale meant for people in wheel chairs, but then i found out they run between $450-2,000. There has got to be a cheaper way to weigh the robot without dishing out so much money. Just to clarify, I am looking to weigh the robot as a whole, not one part at a time. Any methods or general ideas are welcome!
Thank you,
Evan Shegoski