After just finishing typing in 12 pricelists (W x H) of 15 x 11 items I thought of using colour scales to verify the input, sure enough most of my mistypes where highlighted!

It wont catch all errors but quickly points out 52.10 insted of 152.10 and 123.43 instead of 213.43 etc! Which in this case would have been most of the errors!

You only have to highlight the list data and select conditional formatting/colorscales the auto preview will show you without making it permanent!