One year tax transcript. Transcripts directly from the IRS does not need additional evidence. If you submit a signed copy of your return from your tax preparer then you will need W-2 and/or 1099. Also, if you have changes to your income, 6 months of pay stubs or an employment verification letter stating date of employment and salary information.

@Puzzle Head thank you so much!!

I see everyone talk about three years worth of tax documents so they only require the most recent year