Identify
Identify exactly what you have. If you have silver pieces, for instance, the marks on the pieces should tell you the manufacturer and silver content and perhaps the pattern name or number. Knowing the year that your superhero figures were manufactured -- and the model numbers -- will aid you in researching their value. Use collectibles or antiques guidebooks to identify manufacturer, year of production and pattern or product name.
Condition
Condition is all-important in the collectibles market. Assess the condition of your collectibles and be honest with yourself. Damage, flaws or missing elements usually affect values negatively. Understanding the true condition of your items will help you accurately determine its value and avoid disappointments later. Remember, too, that extant repairs, even good ones but especially poor ones, indicate poorer condition and usually affect value.
Guide Books
Consult collectibles guidebooks for values of your exact items or those that are similar. Remember that even small differences in similar items can cause disparities in values. The Completed Listings section of eBay will show recent sales of items like yours.
Collectibles Shows
Go to antiques and collectibles shows where items like yours are likely to be for sale. You can look at price tags and ask experts about your collectibles. Take your items so the dealers can see them. Remember that the price on an item is often not the price the dealer expects to get for it. You'll find that a show devoted entirely to your area of collecting -- sports memorabilia or dolls, for instance -- will yield the most useful information.
Selling
Remember that there are two values for every item. The first is the resale or wholesale value -- the amount you'll get if you have to sell the item. This is usually much less than the other value: the retail or replacement value, which is how much you'll pay in the marketplace to replace an item.