8. Record the correct cost basis when selling stocks.
An unrealistic stock value on your return most likely won't go unnoticed by the IRS. If you sell a stock, be sure to include the correct original purchase price, no matter how far back the transaction was made. Also know the date a stock was purchased, since this is what determines the cost basis and tells the IRS how much profit you made when you sold it. Even if the stock was a gift, don’t guess when it comes to the details. Incorrect info and "guesstimates" are common causes of further questioning. (iStock Photo)