Although the Bible tells us we should not covet property, the plain truth is that we do and we spend lots of time acquiring what lawyers call personalty. Most of us like to own things and nothing makes us happier than to acquire things that are rare, handsome or both. When couples divorce it often happens that dividing the household contents becomes an enormous side show under the big top called equitable distribution of property. For those inclined to have such battles here is some free advice.

Most of what we own is pretty close to worthless. Buy a sofa for $2,000 and take it home. Put it on your front lawn and you might get $800 for it if it’s still wrapped in plastic. Let your kids jump up and down on it a few times and you can halve the price again. Want is appraised? Plan to spend $100-200 an hour so that you have something to fight about.

Having said that, there are valuable things in life. If there weren’t we would not be able to watch Antiques Roadshow on public television. Just about everyone owns a collectible piece of something. But we also tend to misunderstand value and just how volatile the market is.

The good news is that we are not alone. Even people who profess to be experts on personal property often are wildly wrong. This is especially true if the article in mind is rare or unique. The cleanest way to decide value is at public auction. But public auctions are useful but can have their own limitations.

Take the case of the two major auction houses: Christie’s and Sotheby’s. America’s finest collectibles whether tall case clocks or vintage wines are sold weekly by these houses. They have expert staffs to assist sellers in marketing the consigned items and in helping to determine the appropriate price at which an item will sell. Open their catalogues either in person or on line and they will give you an estimate of what any given item is expected to fetch based upon their century or more of experience.

Usually the pre-sale estimates are close to what the object sells for although in times like these you will see the range of possible sale prices broaden. But even the experts can be left dumbfounded on some of the lots. In January, 2007 Sotheby’s had its annual “big” sale of American Antiques. In January, 2007 one such lot was a New Hampshire tea table estimated to bring $7,000-10,000. It was knocked down at $36,000 even though it had been extensively restored. Also stunning was another New Hampshire piece; a fairly conventional bow front chest of drawers that was estimated by Sotheby’s to bring $3,000-5,000. The hammer did not fall until the piece reached $70,000 and that meant $84,000 by the time the auction house was paid. The surprise of the auction was a fairly important dressing table made for a prominent Philadelphia family in 1765. The estimate was not shabby at $300,000 to $600,000. Bidding stopped at just over $4.4 million. It’s not all uphill either. Another Philadelphia piece, a tilt top tea table was expected to fetch $15,000 to $30,000. The bidding never made it to $10,000 and the reserve was not met.

Chances are you don’t have much stuff of this caliber in your household. But the lesson is that appraisers are often as baffled as we are. If you are trying to figure out value, a good first step is to see what you can learn from Ebay by looking for items similar to yours. If you are an Antiques Roadshow fanatic listen carefully to when the appraiser says what an item could or would expect to obtain at auction and what they describe to be the insurance value. The difference is like that between wholesale and retail. A good portion of the buyers at auction are antique dealers. They don’t pay $5,000 for a piece of silver with the expectation of selling it for the same price. They pay $5,000, polish it, put it in a shop they rent, hire sales people to show it off and ask $12,000 for it while you are roaming through the shops in Carmel or Nantucket. That’s how they make their living. Unless you are willing to do what they do; don’t expect that something is “worth” what you see it for in a retail setting. These principles apply in the free market and in valuing assets in a divorce proceeding as well.