I weight myself most days in the morning and evening even though I know that I shouldn't!
Yesterday I weight myself on the sclaes at home, the scales in the changing room of the gym, and the scales upstairs in the gym! And they all said different things .... I think I might stick to my home ones (not that they are the lowest but because I originally weighed myself using those)
You should stick to the same scales as there will be a discrepancy between different scales, different flooring etc, and by weighing on loads of different ones will just play with your head x x