There are those people who receive cash for the work that they do. That is great when you think about how much Uncle Sam does not get, but, in the event that they need a bad credit auto loan, it is the poorest decision that can be made.
Lenders who specialize in bad credit auto loans require proof of income. No proof, no loan, no exceptions. The proof has to be on an acceptable government document. Of course, a W2 is preferable, but 1099-MISC income will be considered if it meets the income-to-debt requirements set by the lender.
If your credit score has slipped and you need a second chance auto loan, then you may want to report all of your income at the end of this year. You may have to do this for a few years, just until you are able to raise your credit score. Too bad that the shysters in Congress will have access to you taxes, but it is a necessary evil if you want to get your credit back on track.