Good luck Mary.
You may be able to find a loan shark (hard money lender) if you have 50% down. You will pay very high fees and a high interest rate, too.
It may be better for you to get working on your credit history. Try http://www.DaveRamsey.com he's sincere and you can take a Financial Peace University class to help you get on the road to fixing the credit.
Check with a mortgage broker or loan officer to determine just what your credit score is. And to determine whether there are any programs that you might qualify for. But if you truly have "bad credit," there won't be any.
You might consider owner financing or a lease-option instead.
Hope that helps.