I think my bathroom floor has little hills and valleys in it because I can weigh myself at three or four different spots in the bathroom and get a couple different weights. I take a rough average if I'm getting a lot of values, but if I get a majority weight, that's the one I use. I only lose a pound a week, if that even, so I know the importance of every pound, but try not to sweat it if I can't get an accurate read.
I look at little things...like how I don't suck in my gut when I'm walking around anymore. That tells me my clothes fit and I feel good in them! Good enough for me.