This article is from the What Every Investor Should Know.
The commission charged for a particular transaction may vary substantially from firm to firm. Most firms maintain an established commission rate structure, which they will apply to a given transaction; however, sometimes they will agree to "discount" their regular rates on large orders or for active customers. In addition, there are firms known as discount brokers that usually charge lower rates, but do not provide extra services, such as research or investment advice. These brokers, generally speaking, offer discounted rates to every customer on every transaction.
Investors should shop for brokerage services as they would for any professional service, keeping in mind that both the amount of service they can expect and the amount of charges they will have to pay will vary from firm to firm.
 
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