Every number from two sources. The second one is usually where the story changes.
I make a rule of checking every keyword, every metric and every claim in two places before it goes into a plan. It's slow for about a week. Then it saves months.
Why two
One tool gives you a number. Two tools give you a range, and the range tells you how much to trust it. When they agree, move. When they disagree by ten times, you just learned the most important thing about that number.
The jump that wasn't demand
A page goes from zero impressions to ninety overnight. Everyone celebrates. Look closer and it was simply indexed for the first time. Nothing changed about the demand; Google just noticed the page existed. A metric is most dangerous right after it starts.
A fast wrong answer beats a slow vague one. A checked answer beats both.
Same with claims. If the site says a feature is automatic, someone should have watched it be automatic, on the devices customers use. Trust compounds. So does the cost of losing it.