By Anthony Enright - of Treasure Hunters Roadshow http://treasurehuntersroadshow.com/blog/

QuoteI hear many amateur collectors of antiques and collectibles say, "This has to be worth a lot of money, it's so old."  This is a common misconception within the realm of antiques and collectibles.  Many people think that just because an item is old it should be worth a significant amount of money.  An antique in the truest sense of the word is anything that is 100 years or older.  While age can have somewhat of an impact on antiquities, there are a few factors that play a larger role in determining the value of an antique.  These factors are rarity, condition, and desirability.
Rarity
How many there are of a specific antique or collectible makes up approximately 50% of the antique's value. Whether it was mass produced or manufactured in limited numbers should be considered, but the true question is how many exist. There are a multitude of antiques that were mass produced, but because of various factors, i.e. the material it's made of, there may not be many existing today.
Condition
In real estate, the old adage is "location, location, location." When considering antiques and collectibles, we say "condition, condition, condition." Condition has approximately 25% impact on the value of an antique.  Look for cracks, chips, missing parts, or defects in the item. Any departure from how it originally appeared and worked will have an effect on the value. An original box that accompanies the item will typically increase the antique value, especially if the box is in mint condition as well.
Desirability
In Economics 101 we learned that supply and demand has an impact on the value or price of anything. Antiques and collectibles tend to be cyclical, meaning different genres of antiquities are desirable at different times. War memorabilia may be currently highly desirable, however 3 years from now it may not.  Desirability makes up the final 25% of the value of an antique.
So the next time you are out hunting for that antique or collectible, remember that if it is rare, in good condition, and something someone has a desire for it may be an item that has significant value.

I agree mostly. How ever there are collections that give the collector satisfaction that can be new items found in guanity . look at hess trucks, gas stations all over sold them, there were billions sold and people still add to there collection every year, Pocket knives are another or maybe you like beer cans  the list is probably longer than single antiques. also some collectors like the feel of a wrench and finds out it was made five years ago and no matter what condition it is in it will never be disposed of    bob w.

My friend Junkin John has a factor to add to all of those. He has a mental list of 'Dead guy toys". A good example is watch fobs. He has been president of the watch fob collectors club in the past. 20 years ago, they had ten times the membership that they have today. The value of collections is way down from what it was and individual fobs, no matter how rare, won't bring much on ebay. The guys that collected them are gone. Most people don't know what a watch fob is. Cool is a very fickle commodity.

All those are factors, but in the end, unless one collects as an investment, not so important as the pleasure and joy of having a thing that one finds attractive.  Nothing is so rare as my grandfather's hammer; there is only one in the world. 

I have a lot of hammers.  The one that was most expensive is a blacksmith made claw hammer that I needed for living history at Sutter's Fort.  I think I paid $35 for it.  Others are varied.  There's another pre-adze eye claw that looks beat up, and the handle is really chewed.  One day it was the closest to hand and I picked it up and went to work.  Despite its looks, it's a good, working hammer.  Not especially rare, not great looking condition, and since I bought it for a couple of bucks, apparently not terribly desirable.  Having used it, though, I won't part with it. 

I like tools with a work history.  I had the rare opportunity to pick up and handle a few of James Marshall's personal tools.  The plane was worn, and clearly showed where he placed his hands when he used it.  Now that one has an expensive history, but I have other tools in much the same condition, tools that show how somebody used them long ago.  I really like that quality in an old tool.

I certainly appreciate a NOS tool in its original box, but honestly, I'd rather have one that has been used, that has done its job.  That's more valuable to me.  I like, too, tools that need some work to be returned to service.  I learn a lot from them.   

Using old tools teaches me about the people who used them and the work they did.  You can assign a value to that, but I don't think it has a price.

Demand is the only thing controlling the value of --any-- object. Period
Supply means nothing, there may be millions available.  Mercedes made a million cars and sold them all for top dollar.
Age means nothing. I have some worthless million year old rocks.  Cartier just got a million dollars for a brand new ring.
  Demand is the --only-- factor.

   When the demand is satisfied, the price goes back to zero if no one wants it.

But it only takes a few anxious buyers creating a demand, to bring the price up. 

One time years ago, I was talking with my old friend Brad about this very subject.
A certain San Francisco bitters bottle from the 1870's was considered common and uncollectible.
Every bottle show would have 2 or 3 on the floor somewhere and no takers at 20 bucks apiece.
  But the first examples of these, the earliest made, the hand applied glop tops, were actually quite scarce.
   Since nobody was looking, these earliest ones were plopped down with the rest and ignored.

  So Brad and me decided, between ourselves, to just take the glops off the market, and see what happened.
Every show we would go to, if there was one of these bottles for sale, we'd buy it.
Guess what?
In less than a year we had corralled the available stock.
There really were only very few of these bottles out there.  6 of them as I recall.
Several hundred of the later tool tops, but only 6 hand applied examples.

    The price of the glops went from 20 to 50 to 200 to $500 in the very next year because once they were all gone, everyone wanted one.

  If one of these early applied top, Dr Henley's IXL Bitters comes up for sale now, it goes on the ==front== cover of the auction catalog.

Demand is everything.
     yours Scott

Branson and ScottG have hit the nail square on the head.  I don't think it could be defined any better.  Branson is right about prices for those who collect for our own pleasure, our own use.  If the price is too high, I don't buy.  After all I'm buying for my own pleasure.  I'm not now nor have I ever bought with an eye towards a profit.  I buy because I like, need it to fill a hole, etc.  That said I also see ScottG idea about demand.  What's rare in one part of the country may not be so rare in another.  Since the southeast was slow to leave horses/mules and go to tractors, there are a lot of plows still available here.  Unless it is rare the prices are around $50.00 to $125.00.  I was at a friends who buys and sells (a dealer) and saw several Oliver walking turning plows on a trailer.  When I asked about them, he replied that they were sold to a man in the mid west and that I could never guess how much he got for them.  When I asked how much, he said '$350.00 each.  They are worth more out there because they don't have as many out there.

I can still remember blacksmiths working as a profession when I was a shirt tail kid in the '50's.  I also remember welding shops that still had forges and anvils as late as the late '70's.  I say that to point out that 4 and 6 inch post vises bring about $75.00 around here.  As a matter of fact I could put my hand on 4 or 5 within 20 miles of me at that price, but I understand that out west they bring $200.00 up.  Supply and demand!!!!!

I also collect Double Cola bottles.  Most of you maybe don't know about Double Cola.  It was a small regional bottler (East of the Mississippi River.)  Before Double Cola developed the ACL (applied color label ie: painted label,) every one pasted paper labels on plain bottles.  You can find Coca Cola and Pepsi bottles with the paper labels but I've had a marker on Ebay for 10 years and have yet to find a paper label Double Cola bottle, The only bottle I need to complete my collection.
Supply and demand!!!!!!

I'm reminded of something that happened almost 40 years ago.   An acquaintance offered a Mayan ritual cup to a friend for $500.  The friend was interested, but asked, "Is it really worth $500?"  The reply was, "It is if you will pay that much."

There's a Stanley #199 on eBay just now.  The price has dropped from $99.95 to $49.97.  Elsewhere, you can get the older ones for $6 to $15.  I wonder where the seller got the impression his was worth $100, or even $50...