building credit for home mortgage loan

[Kat78]

My FICO score is 620: I am new at this so bare with me: I have 10 accounts on my FICO : 3 accounts in past were over 60 days late and 6 acounts showing 30 days late: however for past 9 months no accounts have been late, have set up all accounts to come directly out of checking account so nothing is late. Have mortgage loan, 2 car loans, and student loan that are active. Have an old car loan that was paid off in 2009 but still showing a 30 days late derrogatory mark, and on student loans: was late in 2008 over 180 days but started having it taken from checking account every month and has not  been late since 2008, but still showing marks from 2008. I have no credit cards. My question is what can i do to raise my score, and do I need to apply for credit card. Would like to buid house next year some time, but I know i need to get my scores up.

[RobertEG]

If you already have at least two rvolving accounts, adding another probably will have little benefit in improving your mix of credit.

And the process of applyng could lead to recent inquiries.  Additionally, if approved, the new account will have a zero initital age, and thus lower your average age of accounts.  Unless the added credit limit is substantal, and thus results in a lowering of your overall % util, it might result in a lower rather than higher score.

I would concentrate on removal of all major derogs,which are having substnatial negative impact on your highest-weighted scroring category... your payment history.

GW for rmoval of derogs still showing under paid accounts, and PFD offers on any unpaid delinquent accounts, would most likely bear the most fruti.