Two Numbers, Two Different Questions
When an appraiser values an object, or an AI tool does, you might see two figures: fair market value and replacement cost. They're not interchangeable, and using the wrong one for your situation can cost you money or create problems down the line.
Here's what each one actually means.
Fair Market Value
Fair market value is defined as the price a willing buyer and a willing seller would agree on, with neither under pressure and both having reasonable knowledge of the facts. It's the number that reflects real-world transactions.
This is the figure used for:
- Estate tax filings and probate
- Donating items to a charity and claiming a deduction
- Dividing assets in a divorce or estate settlement
- Pricing something you're selling on the open market
Fair market value tends to be lower than people expect because it reflects what things actually sell for, not what they're listed for, and not what they cost originally.
Replacement Cost
Replacement cost is what it would cost you to buy an equivalent item at retail today. For a watch, that might mean the current authorized dealer price. For a Persian rug, it's what you'd pay at a reputable rug dealer.
This is the figure used for:
- Insurance coverage
- Renters or homeowners policy riders for specific items
- Determining how much coverage to carry
Replacement cost is almost always higher than fair market value, sometimes dramatically so. A vintage Rolex you inherited might have a fair market value of $6,000 based on recent private sales, but a replacement cost of $9,500 based on current retail. Insurance companies use the replacement cost figure because that's what it would actually cost them to make you whole.
Why People Get This Wrong
The most common mistake is using a replacement cost figure to price something for sale. If an insurance appraisal says your grandmother's diamond ring has a replacement cost of $4,000, listing it for $4,000 is likely to leave it unsold for a long time. The fair market value might be closer to $1,800.
The reverse mistake is equally real: insuring something at fair market value instead of replacement cost. If that ring is lost or stolen, an insurance payout based on what it would sell for won't cover what it costs to replace it.
How Tappraise Handles Both
When you photograph an item and run it through Tappraise, you get both figures, with a plain-language explanation of what each one is for. The goal is to give you enough information to act correctly, whether you're listing the item for sale, deciding whether to insure it, or filling out estate paperwork.
For legal and tax purposes, a formal written appraisal from a certified professional is still required. But knowing the rough range before you hire someone saves time and helps you ask better questions.
A Quick Reference
| Situation | Use This Number |
|---|---|
| Selling the item | Fair market value |
| Insuring the item | Replacement cost |
| Estate tax or probate | Fair market value |
| Charitable donation deduction | Fair market value |
| Deciding whether to insure | Replacement cost |
The Takeaway
Neither number is the "real" value. They answer different questions. Fair market value tells you what the market will pay. Replacement cost tells you what it would cost to start over.
Knowing which one applies to your situation is a small piece of knowledge that has a practical impact. Confuse them, and you either underprice something you're selling, underinsure something you're keeping, or file paperwork with the wrong figure.