You can do a quick mite check by getting a dark piece of paper and holding your girl over it. Rub back and forth on her quills to get some "dander" to fall out. Take a look at what fell, you might need some sort of magnification, but if it moves it's mites and if it doesn't it's dry skin. Not very scientific, but it helps give you an idea anyways
I just went to a vet in MA. The "well check" was ~$50, and then a mite check (as Winston had VERY dry skin) was $26 on top of that. He did not have mites, so that was good. He DID scratch quite a bit with his dry skin. Not sure if I counted it, but thinking back he doesn't scratch at all now. And yes, I did the paper thing before I took him in and nothing moved, but I wanted to be sure :lol:
As for what cured his dry skin, I gave him one bath with Aveeno baby wash with Oatmeal. Then I used this stuff the vet gave me for him where I put it on his food. It's a mix of Omega 3's and fish oil but it doesn't smell fishy. People use it on cats and dogs, too. I heard someone on here used "Sunshine Factor" to great effect, also something you put on the food. His skin took about 3 weeks to get better, now it's lovely. I have not bathed him since that once, except for poopy boot washes.
In my weird brain, putting stuff on food to fix the internal problem seems better than slathering their outsides in oil. I mean, if I had lizard skin I would drink more water, I wouldn't just put a load of lotion on, right?
Anyways, hope this helps!