In the battle of good and evil, there is one resource that constantly goes ignored: old tax returns. Although clearly in the midst of a titanic battle of wills between the Avengers and Ultron the first question should be, “what exactly was Tony Stark’s taxable income for the last year?” these things are oft left to the viewers imagination.
Luckily, if you need access to old documentation for your own existential fight for good and evil, the IRS can provide tax return transcripts for the current year and prior three years. They can also provide account transcripts, which are bit more summarized, for 10 previous years.
How much will these important tools in great struggle cost you? Nothing! They’re free! And many financial institutions accept them as proof of income!
There may be more records that the IRS keeps about you, but for things other than returns and transcripts, you’ll probably need to file a FOIA (Freedom of Information Act) request, and those are a bit more complicated. If your arch nemesis is the IRS itself, this might give you Batman-like insight into the circumstances surrounding your IRS issue.