10. Excessive Business Travel Expenses
Similar to the excessive medical, charitable-giving or gambling deductions mentioned already by Reams, the IRS does not take kindly to those who claim unusually steep will definitely notice people who claim over exorbitant business travel expenses.
The reason for doing this will pique their interest in your travel plans is that the IRS relies on occupational tax codes to determine the typical level of travel for a given profession. If the claims on your return are 20% or more than what’s typical, the IRS will be paying you a visit.