what kind of dog do you have and how old is it?
Is it very itchy?
Any other dogs around that are itchy too?
As far as home treatments for mange, you can use a dip called LimeDip. It is very stinky, stains concrete and jewelry, and you want to use it outside. Basically you bathe the dog and then dip it in the LimeDip mixed according to directions. And you let the dip dry on, do not dry or rinse it off. Here is a website that talks about it.
That dip will help with mange and fungal infections. Scabies mange causes intense itchiness, especially at ear tips, under front arms and down back legs. They will eventually lose hair and have scabs and a bad odor. But allergies can look very similar. For flea allergies you have to use a monthly flea prevention for several months and treat the house too. Usually the hair loss for flea allergies starts at the tail base.
Here is a website with a picture of a dog with mange.
But this is after it has progressed for a while.
Hope this helps,