Instructions
Study which world coins are the most valuable and how to generally assess the value of world coins. The Numismatic Guaranty Corporation (NGC) and the Professional Coin Grading Service (PCGS), in particular, are widely respected coin grading services and also make available substantial free information regarding how coins are graded. Generally, coins are graded based on their degree of circulation, amount of tarnish on the coin, presence of features on the coin (e.g. whether Lincoln is completely or only partially clear on the penny) and overall grade received from a professional grader.
Acquire world coins by purchasing them from a local dealer, buying them on web-auction services like Ebay.com, and/or traveling to collector's conventions (some of which may be quite expensive to attend and exclusive). However, be wary of who is selling the coins and the exact coins that you are seeking to purchase. When using a web auction service, request an image of the coins before making a bid and review past information about the seller to ensure that you are getting exactly what you are paying for.
List the value of your coins based on their condition and an assessment by an appraiser. To receive maximum value for your coins, consider having them appraised by either the Numismatic Guaranty Corporation or the Professional Coin Grading Service. Visit the website of NGC and PCGS for more information on how to receive an appraisal on your collection.
Sell your coins to the highest bidder. Contact dealers through NGC or PCGS or sell the coins through an auction house or web auction service. Set a minimum bid level for your coins that is at least more substantial than what you initially paid for the coins and/or ideally at 90 percent of the book value of the world coins.