When we check level, we put bubble level on counter near fridge. Recently put on floor & noticed a difference. Where do most people check? Counter is a lot earlier.
I Check the bottom of the refer and one spot on the corner of a counter top is the same. When level there I then stuck two bubble levels near the steering wheel. One on the dash for side to side and one on the wall for front to back. I use this to check parking sites as I pull into them and after I've leveled out.