I have bad credit and need financing for my business to expand? Does anyone have any ideas on how to do this?

I have a small residential and commercial cleaning business that I am looking to expand. I have been shopping around for financing through traditional lenders, but due to my 518 FICO score and millions of charge-offs, I can’t get fianancing. I have applied to a few non-profits in the state that I live in. I have also been pitching my case to some friends. I don’t have any family that can help. They all have bad credit and so do much of my friends. I really do not know anyone with cash on hand either. I have been looking into getting an angel investor or a venture capitalist, but I do not know if that’ll work. I’ve posted an ad on Prosper and I never get responses. Again, I think that this is due to my bad credit. I am seriously running out of ideas. I have 15 months invested in this and I do NOT want to give up. Does anyone have any suggestions or can anyone suggest a place that can help me? I know I need to fix my credit, but I need the money to do it. Please, please, help!