Originally Posted by
Flyingifr
Actually, there are no "red flags" - you are assuming the IRS computers actually think like people and get suspicious. They don't. All they do is add and subtract, like add up payments against a tax liability and then subtract it from the tax liability. An overpayment generates a check to the taxpayer and an underpayment generates a bill.
The computers don't need to "think like people" they just need to compute standard deviation and or percent change year over year to flag you for audit.