In my early years in the financial business, I must have looked like an easy target for con men and fraudsters of all stripes.

I truly felt like a magnet for questionable investment pitches, schemes and ideas. It seemed as though one out of every three opportunities I was pitched contained some dubious claim or angle.

Once I even met a guy walking around New York City with a briefcase full of diamonds he was trying to collateralize for a huge loan. Needless to say, the diamonds were not exactly as described, and the lender involved was sophisticated enough to ask the right questions, sending the con artist to parts unknown.

Fortunately, I was savvier than I appeared and avoided the worst these financial rogues could throw at me, losing nothing but my time and the expense of a few rounds of drinks and dinners.

In the years since, similar schemes have been exposed on shows such as CNBC's 'American Greed.' Regardless of the amount of exposure, financial cons are constantly morphing, but the underlying principles remain the same.

From everyday, small-time street cons like Three-Card Monte and the Pigeon Drop to Bernie Madoff, financial fraud remains dangerous water for any investor.

Being able to identify and avoid con men is critical for the survival of your portfolio. Here are seven signs a financial opportunity is a scam.

1. It's A One-Time Opportunity.

All financial cons are designed to attract money. Therefore, they may offer low risk and high returns and make it easy to invest. Whenever an offer appears to provide extraordinary, market-beating returns and the salesman tries to make you feel special since you are being allowed to participate, be cautious. Never base your decision on emotion or how much you like the salesman.

2. Big Promises Are Made.

Cons are built on an unverifiable claim that is often a lie. If you cannot independently verify what the salesman is telling you, do not invest, regardless of how appealing the investment.

3. Royalty Is Investing.

Con men are experts at using little-known or fancy words to describe their wares. Technical jargon and mentions of authority such as the Federal Reserve, Top 50 world banks, royalty, shipping or oil magnates and Russian CEOs are sure signs you are about to get scammed. In addition, claims that a certain celebrity is involved in the investment can signal fraud.

4. Act Now.

This is a classic sign of fraud. Anytime someone rushes you to sign a contract and send money, it is generally a fraud. This rush is to prevent you from performing due diligence. They want you to invest on emotion.

5. Your Money Counts.

Always ask yourself why the promoter needs your $10,000 when he could bring in $100,000 or even $1 million at a time due to the success of the investment program. The reason why they target the smaller investor for sophisticated investments is that the little guy is less likely to complete due diligence.

6. Bet The Farm.

If anyone ever requests you to 'bet the farm,' 'mortgage your home' or invest your life savings, cut them off immediately. No legitimate financial salesperson would suggest such an extreme risky action, no matter how appealing the investment.

7. It's A Guaranteed Investment.

Whenever a salesperson stresses that you money is 100% safe, in addition to earning high returns, the person is lying. There is no sure thing in the investment business and risk is always equal to the potential reward.

The Investing Answer: When approached with an investment opportunity, never immediately agree. Rather, say: 'This looks interesting. Can you provide the details in writing so I can learn more about the opportunity?' If the salesperson says anything other than 'OK' or tries to pressure you to commit, walk away. That's a sure signal that everything isn't 100% legit. Remember, the con artist relies on your emotions.

In addition, if you have any reservations or concerns, always have the offer reviewed by an unbiased third party. Just a little due diligence can protect you from almost every form of financial fraud.