Where can a buyer with bad or no credit get a mortgage?

[Jodi M.]

We just finished a flip house and took a current tenant through. They fell in love with it and went to the bank the next morning. Unfortanitly they have low credit and didn't qualify.We are willing to finance up to a 10% downpayment. Are there any banks or lenders that would loan to first time buyers with credit around 600? Selling price is $70,000. Thanks for any ideas!