IRS apparently audits people who are self-employed more than employees of a big corporation. We have had three home-based businesses in our home, not to mention my now going-out businesses of merchandising and mystery shopping. We have been audited two or three times. There wasn't anything obviously amiss, but I think one time we had to pay but it was years ago so I don't remember details. I'm not the tax preparer in the family. The sad thing is that my husband has been doing income tax reports since he did one for his mother at age ten, so it's not like he was making mistakes. He has also done them for other people. Another time, we had some records come in late that my husband added to the amended report after we were audited, so we came out better than before.
Last year, for the first time, I gave my husband a list of miles traveled while mystery shopping, but he refused to use them on the income tax report because I had just taken where I'd been and added miles I knew I'd traveled rather than writing them down every day. Once burned, twice shy. The daily part would drive me crazy. I know the exact mileage to most of my stops, door to door.
I think that a person who has an occupation (such as teacher or receptionist, for example) that can be listed as the main one that does not include something that would attract the attention of the average IRS agent would do better. I know someone in politics (not as a candidate) who was audited several years ago when our state was trying to remain Democrat. She learned that a political enemy reported her to IRS. My friend was self-employed and had not done anything wrong. The culprit accidentally revealed knowledge of the audit in conversation. It just goes to show that, just as a neighbor can report you to Child Protective Services out of revenge (also happened to a friend who was homeschooling), so can political enemies report you to IRS. I guess they have to investigate even if there is nothing wrong.