Audit Guarantee: What does it really mean?
A non-CPA "tax preparer" may accompany you to an audit to answer questions concerning their preparation of your return, but cannot appear for you and cannot act as your legal representative. You would still be required to appear personally, and could be exposed to uncomfortable direct questioning by the auditor. A nervous taxpayer can make mistakes or, inadvertently, just present true information in the wrong way.
A CPA tax accountant may go to an audit in your place as your legal representative, having power of attorney. You do not need to be present, nor take time off from work, and be subject to a potentially stressful situation. Your CPA may answer questions for you, present information, and prevent the auditor from directly questioning you. The purpose of this is not to hide or conceal anything, simply to have the matter handled smoothly by a professional CPA, who knows all of the rules, who is professionally respected by the IRS, and can skillfully negotiate the best resolution for the client.