But if you can't afford to bring in a pro, here are some tips that will you help you survive your audit.
1. Don't ignore the audit.
The worst thing you can do is pretend like an audit letter never came. Instead, follow the instructions on your letter, with particular attention to replying within the specified time frame. Doing so will help you avoid getting off on the wrong foot.
2. Don't be defensive.
Just because your return gets chosen for an audit doesn't automatically mean you've done anything wrong. The IRS chooses some audits based on a computerized scoring system, which looks for certain elements that commonly lead to tax abuse. In other cases, records from your employer or from financial institutions that pay you interest or dividend income may provide information that's different from what you've listed on your return. Regardless, it pays to keep an optimistic viewpoint, as many taxpayers get through audits without owning a penny -- and sometimes even get extra refunds back.
Usually, the audit letter will note specific items the IRS is interested in. Gather and organize your records on those items to support your claims, and if you don't have documentation, take steps to get it before your audit date. Without records, the auditor may simply rule against you. Moreover, make copies for the auditor to take so that you can keep your originals.
4. Bring only what you're asked for.
Just like lawyers tell people not to volunteer extra information on the witness stand, be sure to stay on point in your audit. Don't talk about unrelated topics, and don't bring additional information or records to an audit if the IRS didn't request them. That way, you'll be more likely to keep the auditor focused on the specific issues in the audit and avoid a wild goose-chase that could result in extra issues coming up.
5. Being nice can make a big difference.
IRS auditors are used to be treated like dirt, but that doesn't mean they like it. Just as being nice to a police officer can turn an expensive speeding ticket into a warning, staying courteous with your auditor can sometimes mean the difference between winning and losing.
For more on the audit process, be sure to check out IRS Publication 556 as well as this simple guide to your rights as a taxpayer.
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Motley Fool contributor Dan Caplinger has dealt successfully with audit requests in the past and hopes he will in the future as well. You can follow him on Twitter @DanCaplinger.