Historical Data: This is probably the best indication of how a stock will do in the future. I made a fortune buying a Dow 30 company as they rise and fall with the average like clockwork. When the Dow was down real low, I purchased all I could get, knowing that the market would eventually turn around.
News: Before you invest in anything you should understand what the company or commodity is doing in the news. Even something that does not seem significant could be if the news outlets get a hold of it. A stock may look like a steal until you read that their main product just had a safety recall or something similar.
Tax Fees: Some investments do not pay much, but have no tax consequences like municipal bonds. If you are considering this, make sure you understand exactly how much in taxes you will save by taking the smaller return on your investment. There are some great calculators on the Internet that will give you this information in no time.
Charts: Some people live and breathe for the charts and do very well at it. However, this should only be used as one indicator and you should not trust them completely. The charts always work perfectly until they do not, and you are left wondering why. However, they can be used as a basis and use your other research to complete the whole picture.
Running the Company: Always know the person running the company that you are going to invest in, before you make the purchase. Find out what there management style is and what they typically do when they take over a business. Even if they were never in the top job before, you can usually put it together based on how they ran other business units.
Understanding: Be sure you understand what the company does and what could happen that would make the company do well or go under. You should never invest in anything you do not completely understand. This is the best advice I can give you. If you do not know what is involved with a stock, you will not have any good understanding of when you should buy and when you should sell.
TV Personalities: I do not think these guys are gurus or even good at what they do. However, considering other people thing very highly of them, they do have the power to affect stock prices. If one of these guys wakes up in the morning and says company X is no good, the company will lose some shareholders and the price will go down. Make sure you know where everyone stands.
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