Pricing Check - based on a dynamic date range

Hi

I've tried to post this twice but i computer seems to be messing up, so apologies if this re-appears mulitple times!

I have a table with pricing for certain products with a specific date range, to the right of the table in columns are a list of dates with the prices by date.
What i need a formula to do, is to flag if any of the values in that date range are incorrect (regardless of which column within that range)

The first column of dates will always be the date that the file was opened =today()

i could do it with a set range and an average cost, but as i will be running this check daily, i need it to be dynamic, as everyday forward the range will get smaller,

any help i'll gladly take!!

thanks
Adi

thanks alansidman, hopefully trying to keep away from VBA were possible for now, i may well come back to it though!

Fotis1991, which will be helpful for identifying were the error is, ideally i need it to bring a true/ false or anyother comment into the P6 price error field (F3 / F4 etc)
so that we can drop into into another worksheet to run off this.
Unless anyone knows of a way to count coloured cells, within that date range, i've never got that side of excel to work!

Thanks Fotis,
that worked a treat, knew i was overthinking it, thats a massive help!!

Adi