With regards to credit qualfying, you will need a 620 credit score in order to qualify. It's important to understand why your score is where it is and the steps needed to boost it to an acceptable range. I'd be more than happy to discuss matter further.
If your credit score is in the mid 600's, you may be able to get a mortgage. Otherwise speak to a mortgage broker to see what you can do to repair your credit in order to qualify for a mortgage. Hope this helps!