The "Buyer Beware" warning applies especially to a business or real estate held in a self-directed IRA.
For example, a typical requirement of lenders is that any loan be personally guaranteed by the borrower. The personal guarantee of a loan in a self-directed IRA was recently ruled upon by the Tax Court, with disastrous results. The penalty in the Tax Court case was 20% of the tax underpayment with no cap on the amount of penalty!
Learn more about Self-Directed IRAs: