Fair market value (FMV) is the price that property would sell for on the open market. It is the price that would be agreed on between a willing buyer and a willing seller, with neither being required to act, and both having reasonable knowledge of the relevant facts.

Source: IRS Publication 561

This definition is the standard the IRS uses to determine if an item sold or donated by you is valued properly for income tax purposes. It’s also a definition that’s open to interpretation. If the IRS decides your FMV opinion is incorrect, you’re not only subject to more taxes, but also penalties to boot.

Here are some tips to help defend your FMV in case of an audit.

Understand when FMV is used

FMV is used whenever an item is bought, sold, or donated that has tax implications. Some of the more common examples are:

• Buying or selling your home or other real estate
• Buying or selling personal property
• Buying or selling business property
• Establishing values of other business assets like inventory
• Valuing charitable donations of personal goods and property like automobiles
• Valuing the barter of services
• Valuing transfers of business ownership
• Valuing the assets in an estate of a deceased taxpayer

Ideas to defend your FMV determination

To help defend your FMV determinations, consider the following:

Properly document donations. FMV of non-cash charitable donations is an area that can easily be challenged by the IRS. Ensure your donated items are in either good or better condition. Properly document the items donated and keep copies of published valuations from charities like Goodwill. Don’t forget to ask for a receipt (confirmation) of your donations.

Donate capital items like automobiles to the correct places. You may use the FMV of a donated automobile, but only if the charity receiving the automobile will use it themselves, or will provide it to someone who will use it. Otherwise, the FMV of the donated vehicle will be limited to the amount the charity receives when they re-sell it. So be careful if donating to places like Kars4Kids or your donation value could be limited!

Get an appraisal. If you sell a small business, a collection, artwork, or a capital asset, consider obtaining an independent appraisal of the property prior to selling it. While still open to interpretation by the IRS, getting a third-party appraisal can be a solid basis for defending any differences between your valuation and that of the IRS.

Keep copies of similar items and transactions. This is especially important if you barter goods and services. If you have a copy of an advertisement for a similar item to the one you sold, it can readily support your FMV claim.

Take photos. The condition of an item is often a key determinate in establishing FMV. It is fair to assume an item has wear and tear when you sell or donate it. Visual documentation can be used to support your claimed amount.

Keep good records. Keep copies of invoices for major purchases and retain bills for any improvements. Make sure your sale of property includes a dated bill-of-sale that clearly states transfer of ownership and the amount paid for the item.

With proper planning, establishing the fair market value of an item sold or donated can be done in a way that can be defended against a challenge from the IRS.