Have you got one or a number of negative accounts that you intend to get rid of? Don't think of breaking into the offices of the bureaus to alter it. I know you won't. But your intelligence and how you apply it in writing your dispute letter is the important thing here.
Rule one, never dispute more than one item on a letter. If you violate this rule, don't be surprised if nothing is done in that regard and the agency will have cause for neglecting your request on the grounds of frivolity.
You do not need excessive use of grammar or flamboyant words to impress the bureau. A simple grammar used by a fifth grader would do so long as you state what it is you noticed on your file and what you want them to do.
Notify the bureau that you are aware that the Fair Credit Reporting Act gives you the right to challenge any incorrect information which you perceive as negative and injurious to your rating.
Include important personal details such as your full name, credit card number, social security number, a copy of your driver's license, a copy of your credit card, your house address, your phone number and your email address. But NEVER send your letter by email or via the internet.
You should use standard mail that you will be able to track in sending dispute letters to bureaus in situations as this, and always remember that you should challenge most recent and most damaging accounts on your file first before the rest.
Reporting agencies are required by law to respond within 30 days upon receipt of your letter, and if they do not conclude their investigations after expiration of the period, they are required to delete it.
If, however, you find it cumbersome drafting tons of letters and waiting for responses on several accounts you want bureaus to address, you can as well hand the task over to a credit repair agency.