TL;DR: Four things set an antique's price: what it actually is and who made it, its condition with the original finish intact, how rare it is against how many people currently want it, and its documented history. Check real sold prices on eBay filtered to completed sales, plus auction results on LiveAuctioneers, rather than asking prices. Do not refinish it first, because the original surface is part of the value. Pay for an appraisal if the plausible number is over about $1,000.
My grandmother had a walnut side table that everyone in the family assumed was worth something, on no evidence whatsoever beyond it being old and having belonged to her.
It was worth about $110. What made the real money in that house was a set of six chairs nobody had thought about at all, because the maker's mark was underneath a seat and none of us had turned one over.
That is the whole problem with pricing antiques without an appraiser. The value is rarely where the family sentiment is, and it is usually written somewhere you have not looked.
The four things that set the price
Authenticity: what is it, and who made it.
This is the one that changes the number by a multiple rather than a percentage. A period piece and a good reproduction can look identical in a photo and differ by ten times in price.
So before anything else, go looking for marks. Underneath drawers, on the back panel, under seats and tabletops, stamped into hardware, printed on paper labels inside case pieces. Photograph anything you find, even if it means nothing to you, because it will mean something to a search.
Then look at construction. Hand-cut dovetails are irregular and few; machine-cut ones are uniform and many. Original screws have off-center slots and inconsistent threads. Saw marks that run straight are older than the circular arcs left by a circular saw. None of these settle it alone, and together they tell you roughly which century you are in.
Condition, and specifically originality.
Here is where most people accidentally destroy value before selling, so it is worth being blunt.
Do not refinish it. On a genuinely old piece, the original surface, the patina, is a large part of what a collector is paying for. Stripping it removes the evidence of age along with the finish, and it cannot be put back. A dresser worth $900 with its original surface can be worth $300 sanded and polyurethaned, and the person who did the sanding thought they were helping.
Clean it gently, wax it, tighten loose joints, and stop there.
Original hardware matters for the same reason. If someone replaced the pulls in 1985, keeping the originals in a bag inside a drawer is worth real money. Missing parts hurt more on antiques than on modern furniture, because they cannot be sourced.
Rarity, but only where there is demand.
Rare and valuable are not the same thing, and this is where a lot of family estimates go wrong.
Brown furniture, meaning traditional dark wood dining sets and case pieces, is genuinely old, genuinely well made, and has collapsed in price over the last two decades because very few people want it. Meanwhile mid-century pieces from the 1950s and 60s that are neither rare nor especially old sell for multiples of what the antique version does.
Rarity multiplies demand. It does not create it. An extremely rare example of something nobody collects is worth what the wood is worth.
Provenance.
Documented history: who owned it, receipts, photographs of it in a known house, letters.
For most household antiques this is worth nothing and you should not chase it. For a small number of items, it is worth more than the object. If there is paperwork in a drawer, keep it with the piece.
How to actually look up a number
eBay, filtered to sold listings. This is the single most useful free tool available to a private seller and most people never touch the filter. Search the item, then filter to completed and sold. Asking prices are fiction, because anyone can ask anything and the listing that sat for two years at $4,000 tells you nothing. Sold prices are what someone paid.
LiveAuctioneers and Invaluable. Auction results across hundreds of houses, searchable, with photos. This is where you find out whether your category is currently moving.
Worthpoint. A large archive of past sale prices. It is a paid subscription, which is worth it for one month if you are clearing a whole estate and worthless for one table.
Then adjust down. Auction results are hammer prices at events full of dealers. A private local sale usually lands 30 to 50% below them, and faster.
What AI can and cannot do here
I build AI pricing into a product, so I will draw the line clearly rather than sell past it.
A model looking at photos is good at category and era. It will recognize a style, place it roughly in a decade, and give you a range for that category. That is genuinely useful as a starting point, especially across a whole house where the alternative is forty hours of manual research.
What it cannot do is authenticate. It cannot tell a period piece from a well-made reproduction, because the distinguishing evidence lives in dovetail irregularity, screw threads, and wear patterns that a photo does not carry reliably. It also cannot read a maker's mark you did not photograph.
There is a broader version of this in can AI actually find comps for used items, and the short form is: use the estimate to narrow the range, and use sold listings to settle it.
When to pay a professional
Pay for an appraisal when the plausible value is over roughly $1,000, when the item is being insured or split between people in an estate, or when authenticity would move the price by a multiple rather than a margin.
An appraisal runs a few hundred dollars in most places. On a $300 table that is absurd. On a piece that might be $200 or might be $6,000, it is the cheapest part of the transaction.
Free alternatives worth knowing: many auction houses will give you a free preliminary opinion from photos, because they want the consignment. That is not an appraisal, and it is enough to tell you whether you need one.
The practical order
Photograph every mark you can find, including the ones you do not understand. Do not refinish anything. Search sold listings before you form an opinion. Get a free auction house read on anything that might be over $1,000. Price the rest 30 to 50% under auction results and sell it locally.
And turn the chairs over. That is the actual lesson from my grandmother's house, and it took us a week to learn it.
If you are clearing a whole estate rather than one piece, how to run an online estate sale yourself covers the logistics, and selling collectibles online without the grind covers the smaller valuable things that get lost in a house clearance.