Whether you're buying coins as an investment ... selling coins and looking to just break even ... or trading coins and hoping to make a good deal, you'll maximize your return if you follow prudent guidelines.

Here, then, is my list of the 10 most important investment pointers:

A publication I recently read gave some rules of thumb on how to negotiate in the coin market. The advice was downright awful. One of the rules, for example, said buyers should always start by offering the seller a set percentage below the asking price. This disregards the fact that the asking price could be far above the coin's true market value.

If a coin is worth $1,000 and someone is asking $10,000 for it, you wouldn't want to offer $5,000. On the other hand, if a coin is worth $1,000 and someone is offering it to you for $50, you wouldn't want to jeopardize the deal by haggling in an effort to get the price down to $25. You would simply say, "OK, $50 is fine," buy it for $50 and sell it for $1,000.

If you don't know what a coin is worth, you shouldn't be negotiating for it in the first place. If you do know what it's worth, you have a big edge over other people who don't.

More so than in almost any other field, quick action pays big dividends in the coin market.

If you buy a coin through the mail and you feel it has been overgraded or misrepresented ... or you buy a coin from a dealer at a coin show or coin shop and then decide you just don't like the coin ... act quickly and return it. The longer you wait, the less chance you'll have of getting your money back and the greater the chance your return privilege will expire.

Conversely, if you have a coin that rises in value quickly, go to the cash window and celebrate. Sell it and take your profit. Don't wait; do not hesitate.

I've heard people say that if you're an investor, you should become a collector and gain an appreciation for the historical, cultural and artistic significance that rare coins represent. That's perfectly fine. However, I also know a number of solid collectors who don't pay attention at all to the very real financial implications in their coin transactions. If they like a coin, they buy it with little or no regard for the price.

As president of Scott Travers Rare Coin Galleries in New York City, I love dealing with people for whom money is no object--collectors who are willing to pay any price for a coin. That's wonderful for me. But taking that kind of approach may not be so wonderful for you as a coin consumer.

If you're a collector, I strongly recommend that you learn all you can about coins' financial implications. If you have a coin that's a duplicate in your collection, go sell it and see how it feels to make a profit. On the other hand, if you're an investor, you should indeed learn about the cultural aspects of coins and learn to appreciate them as works of art. By doing so, you'll gain an understanding of why other people value them--and that will prove helpful in assessing their value yourself.

The collector/investor is the emerging breed of coin buyer and will be, in years to come, the predominant breed of consumer in this industry. To maximize your success as a coin buyer, you will need to possess both a collector mentality AND an investor mentality. It's not to your advantage to be exclusively one or the other.

This sounds like pretty obvious advice, but also like something that's easier said than done. It's really not all that difficult, though; all you have to do is use your common sense. If coins are increasing in value, you should sell into rallies. If coins have declined dramatically in a very short period of time, that might be a good time to buy.

In general, I recommend that you cost-average. No one can outguess the marketplace; for that reason, you should buy your coins systematically over an extended period of time. If you have $10,000 to spend, don't spend it all right now, thinking you can outguess the marketplace. Nobody can. Take $1,000 or $2,000 a month and spend it that way.

This isn't as ridiculous as it sounds.

Many people buy coins simply as commodities. In the course of doing so, they may have ordered a thousand 1881-S Morgan dollars certified as Mint State-65, and the coins may have come in a box from a dealer who sent it through the mail. When the time comes to sell the coins, they may open the box and discover that instead of the 1,000 coins they ordered, they actually have only 575. And the dealer may no longer be in business.

You can't count your profits if you can't count your coins.

Speaking of counting coins, if you buy rolls of coins, make sure that you get full rolls. And if you show one of your rolls to a dealer, make sure that the dealer doesn't palm one of your coins and keep it for himself.

If you have a certified coin which is high-end--which is very close to being the next-higher grade or perhaps really IS the higher grade--it would be to your advantage financially to crack that coin out of its holder and resubmit it to a grading service. By getting it recertified in the next higher grade, you might reap an instant profit of several thousand dollars.

David Hall, founder and president of the Professional Coin Grading Service, recently admitted publicly that a number of coins graded Mint State-67 or Proof-67 by PCGS in the past might be graded 68 if resubmitted now. So go ahead: Resubmit your certified coins if they're nice.

Knowledge is power, and if you're not informed--if you're in the dark--when it comes time to go to the cash window and celebrate, or when there's a significant buying opportunity, you're likely to miss the boat.

Speaking of books, the third edition of my best-selling book "The Coin Collector's Survival Manual" will soon be released in a new third edition, and I strongly recommend that you buy it and read it. You also should be reading newsletters and similar publications. The Certified Coin Dealer Newsletter is an excellent publication and will help you keep informed of market conditions. And, of course, you should stay on top of all the latest developments by reading periodicals such as COINage.

Take all your off-grade modern rolls, all your common coins, all your out-and-out junk and sell them. Better coins offer far greater economic opportunities. Coins which are scarce today can become rare in the future, and coins which are rare today can become rarer. Coins which are common now will remain common in the near future.

By the way, at the risk of offending the very fine people at the United States Mint, I include in the "common" category just about every modern U.S. commemorative coin-- that is, every one issued since 1982.

I'm purposely putting this recommendation near the end of my list, rather than at the top, because I don't want you to use grading services as a crutch.

Certification is extremely important in the current marketplace. Many buyers and sellers won't accept coins today unless they're certified--and it's hard to argue with their reasoning. The grading companies serve a vital function by providing informed judgments on rare coins' level of preservation and, in most instances, guaranteeing the accuracy of those judgments. They remove not only the guesswork but also much of the risk that used to exist.

At the same time, however, you should always keep in mind that when you buy certified coins, what you're really paying for is the coin and not the plastic. The certification gives the coin greater liquidity, but the coin should also stand on its own merits. It should be attractive, pleasing to the eye and otherwise desirable even without the holder. In short, the certification should serve to reinforce its desirability.

If you buy a coin for $10,000, drop it on the street on the way home and it gets a scratch on it, it may be worth only $1,000 by the time you reach the front door. That can be devastating--just as devastating as paying 10 times too much for a coin in the first place.

Similarly, your coins can suffer serious, permanent damage AFTER you get them home ... or put them in your safe deposit box ... if you don't take proper precautions to see that they're safely stored. Make sure to store your coins in a dry, stable environment and, if possible, make sure that each coin's surface is free from airborne pollutants before you put the coins in long-term storage.

You also need to exercise proper care and judgment in the way you handle your coins. When removing coins from holders that have staples in them, always be careful to remove the staples first. And never use your fingers--your bare fingers--to hold the front or back of a coin; always hold the coin tightly by its edges.

You owe it to future generations of collectors to maintain your coins in the same level of preservation in which you received them. You also owe it to yourself--for if you don't, you'll pay a heavy penalty financially.

Follow these tips and you'll find they're a perfect 10.

Ignore them and you may simply end up behind the eight ball.