Many of the more well known pocket watch makers, like Waltham, Elgin, Hamilton, etc, are fairly well documented and so it's fairly easy to put a value on them, even if it is only a rough guide. Where it gets more difficult is if someone brings in a lesser known watch that isn't traded all that often. Putting a value on a pocket watch like that is almost guess work.
This is where sentimental value comes in. If you have a watch that is well known, you know what model number it is and you can accurately date it, then you can fairly accurately state what sort of price it will fetch. Of course, some people don't care what their pocket watch is worth in purely financial terms as the watch holds some sort of sentimental value to them. This only becomes a problem when they wish to sell, which is when reality hits home and accepting market value may not be acceptable.
This was demonstrated a while ago when someone brought in an old 1913 Waltham for repair. The repair itself was quite easy, but was still going to cost a couple of hundred dollars, which is probably what the watch was worth. Still, the owner's instructions were clear, "Just fix it!"
Obviously there was a story behind the watch, so when the owner came to collect his watch I asked him about it. It turns out that the watch had seen battle with his Uncle many years ago and had been passed down to its new owner. Luckily the new owner was quite happy to take good care of it, even being willing to spend a couple of hundred dollars to keep history alive.
As the price of precious metals increases, and I see no reason why that should stop given the U.S. obsession with printing money continues, so the value of pocket watches and any antique made from these metals will also increase. Hopefully we will not see a situation where the value of the metal in the watch is worth more than the watch itself, but unfortunately this does appear to be the case quite often now.
People that bring me watches made of gold or silver always want to know the value of the pocket watch. Often it is easier just to quote the metal price, which is easier than looking up the market value of the watch, which I generally know will be less than the metal price alone.
Ignoring the present situation of precious metals outpricing the object, the price of any item, including pocket watches and watches, is based on Supply and Demand, what its made of, which manufacturer made it, and when it was made. The production run has to be taken into consideration as well, of course.
There is one thing that will never change though when considering the value of pocket watches. Quite simply, they are not being made any more. Every year hundreds of thousands of pocket watches get consigned to the scrap heap, and unfortunately this is gathering pace with the high metals prices.
Unless the world falls into another severe depression, the Demand for these watches is increasing and the Supply is decreasing! All things being equal, antique pocket watch value will increase as time goes by.
Insurance valuation is usually based on replacement value - if you had to replace the item from a retail source, what would it cost? This would be a pocket watch value plucked from a reputable pocket watch guide book, for example. Insurance values are generally higher than free market prices.
Keep your eye on eBay auctions and keep track of prices; soon you will feel more comfortable in your decision making process and over time will learn how to make quick "guesstimate" appraisals on-the-fly. Take a look at this photo below: The person selling this item said that this watch was in "perfect working order". Can you spot how I knew that the person was being less than honest with me? (This was an eBay sale). Take a few moments to study the photo...
Can you see it? (Click pic for bigger picture)
Take a look at the hour hand. See how it bends downwards? It is in fact being pushed by the minute hand so there is no way that the watch can be said to be in "working order". This is a problem with buying sight unseen, you have to ask questions before committing. After the event it is generally too late.