Help Vega from skin condition

Vega is my dog, she's currently suffering with a skin condition. I'm not sure if it's an allergy to fleas or something worse. She scratches constantly now. My once carefree, fun-loving best friend only has time to scratch and whimper 24 hours a day. Her once beautiful husky heeler coat is now hairless in spots and dingy. She's flaky and there are scabs on her entire body. It breaks my heart.

She's my best friend and protector, we've been through so much together. We've experienced homelessness together, been hungry, cold. You name it... that's why I won't turn my back on her now. And before you tell me to get rid of her. We are in a stable home now, she never goes hungry anymore but I cannot afford the vet bill...

I bathe her every week in oatmeal dog wash and dawn. I've tried apple cider vinegar. Nothing stops the spread of this rash. I don't know if it's flea dermatitis or an allergic reaction but there seems to be a pattern with the animals in my area because a few of them have the same issues, a pitbull does, and a cat next door...

I'm trying everything I can to get her relief from it but I can only do so much without a vet. She's the only thing that calms my panic attacks. She's stood up against mean people and abusers for me. She's went through horrible situations for me and never left my side. I panic without her and I hate seeing her in any discomfort. Please, anything helps at this point.