Mange

Question
My dog is an adult, female, BlueHeeler who lives outside.  She has what looks like mange ALL over, except not on her back that I have seen.  I noticed some dry scaly spots on the tops of her feet and at the back of the "elbow" joints a few months ago and had no clue what it was.  I passed it off as old age but continued to notice her behavior and watch the spots.  I have been away from her for a while (my parents fed her and cared for her) and when I saw her Sunday (Easter) she looked...not good.  Thin, moving slow and lots more scaly spots in big patches.  -legs, hips, under her tail, groin/belly area, chin, cheeks, neck and a little less noticeable but behind her ears too.   Also her vaginal opening looks swollen.  Could that be because she has gotten so thin, old age (she's 10 1/2 years old) or could it be inflammation from this skin infestation?
I've been reading about mange and I think she has Sarcoptic mange.  My local vet supply suggested I use a product called Nu-Stock (Sulfur 73%, Pine Oil 2%, Mineral Oil 25%).  I gave her a bath, allowed her to dry and applied the Nu-Stock.  She has so much skin irritation over so much of her body it took the whole tube of that sulfur solution to cover all the affected areas.  

She experienced obvious instant relief from this.  I watched her relax.  She licked my hand, relaxed again and fell asleep.  For several hours her pattern was get up to go drink/or eat/or potty then go back to her spot lay back down and relax.  She still scratched a little occasionally but this provided obvious relief instantly (even in the places that were bleeding) and soothed her so well that she was able to relax.  She is grateful - licking my hand.
I am taking her to the vet this morning!
Mostly because there is so MUCH irritation.  I want to know what the vet should do, as in, what to expect.  I expect they will shave her and examine her whole body.  Will they do a complete physical exam like blood/urine samples? Will I have to ask them to do these things?  Should I?  Since this is caused from mites do they suck blood like fleas or ticks?  Should we be concerned about anemia?  ...or anything else as far as illness since she has such a large amount of her skin affected?
Also, I am concerned about the amount of product I used (had to just to cover the irritated skin I found).  The tube is a 12oz container.  She has licked it a few times during the night but I stopped her each time (I slept about three hours so I wasn't watching her then).

This morning she is moving much more freely and seems "happier".  That's a great feeling!!  

Last question: Should I look for a specialized Vet?  I'm worried about my dog and I read a little of your bio that says you do dermatology so I'd love to have your advice!  Thank You!!

Enjoy Your Day!

Answer
It is fairly easy for the vet to diagnose mange.  It requires a scraping of skin examined under the microscope.  It is unusual in older dogs, though.  Usually there is an allergy with a secondary bacterial or a yeast infection as well as sores and scabs from self trauma. If the sulfur helped, it could have killed mites or it could help quell infection.