Equifax, TransUnion, and Experian are the most popular options, as they provide a detailed breakdown of your credit history. FICO, on the other hand, only provides a score.
If you’re seeing a delinquent payment on your TransUnion report, you need to either pay the amount (if it’s valid) or contact TransUnion to report the issue as fraudulent.
If you’re planning on buying a car, you should check all your credit reports to see how you can improve your credit score. Paying down debt and paying off any delinquent accounts should make you a more viable loan candidate.