Cat with Skin Problem - Iodine?

I have a 7 month old 9 and a half pound kitten. He has a skin condition all the way down the back of one of his hind legs, in a line. The hair is missing there, and there are a couple of small red crusty spots. Not bad enough yet for a Vet visit, I want to see if I can clear it up myself. Trying to avoid the Vet anyway because half the time they don't really know whats going on so they will conduct numerous expensive tests.

I have been spraying on antiseptic antifungal spray For Cats for a few days but I'm not sure if it's helping and he licks it off anyway. I'm not sure if this is a Skin Fungus? Or Skin Mites?

I have been giving him Colloidal Silver in his water for a couple weeks which has had no affect on his skin.

I have heard that Iodine will kill both Fungus and Skin Mites. Is it safe to use Lugols Iodine on his skin? Do I have to dilute it? Or is there anything better?

Thanks to anyone that responds!