Good morning Dana,
Most Lenders require a minimum credit score of 640 in today's lending environment, although some Lenders will lend on a 620 credit score. While your score is not so terrible, it is unlikely you could be approved for mortgage financing with that credit score at this time.
AND, if you meet a mortgage professional claiming to assist you with this low score, turn and walk away. Your score indicates there are serious issues on your credit history that you need to address before you take on the responsibility of owning a home and paying a mortgage. I strongly recommend you take the time to put your financial house in order before you take on the challenge of homeownership.
First, settle any outstanding debt. If you owe money on collection accounts, charge-offs and/or judgments, make payment arrangements and get these accounts paid promptly.
Next, begin rebuilding your credit. If you have current accounts with good payment histories, or even some previous late-payment-blemishes, make sure you continue to pay those accounts on time. If you do not have any existing credit accounts then you'll need to establish several in order to create a viable credit history.
I have found that CONSUMER ACTION is an excellent resource for objective advice on all things credit related. You'll find free and sincere advice on everything from settling collection accounts to rebuilding credit to building credit from scratch on their website. https://www.consumer-action.org
Beware of anyone offering to "repair" your credit! The Federal Trade Commission issued a stern warning last year that such offers are scams. Find more from the FTC HERE: http://www.ftc.gov/bcp/edu/pubs/consumer/credit/cre13.shtm
The best way to buy a home is to have a decent credit history combined with sufficient Income and Assets for a home purchase.
The best way to have a decent credit history is to settle negative outstanding obligations and pay all your bills on time for at least two years.