Dachshund with bald patch and shedding?

Ok, my husband drives a truck and goes to gas wells around our area delivering fuel. Yesterday he went to one that had a dachshund dog that was dropped off the day before. My husband and I being softhearted for abandoned animals, he brought it home. She looks older, mostly reddish brown reg. length hair with some gray around her mouth and down her back. She looks like she has been heavily bred, as her teets are very saggy and feel like just getting over nursing puppies.
Now for the question, Around her tail, mostly on her back towards her tail, she has a small bald spot, and is shedding. I have heard that if you breed a dog too late in age it can stress them and cause them to lose hair. The skin on the bald area, is not swollen, flaky, or anything like that, just skin with no hair. I was wondering if this could be normal for the situation, or if it could be mange.
We have never had a Dachshund before, but have fallen in love with her, such a good temperment.
She seems to like being outside, is it ok for this breed to be an outside dog??

Also we live way out in the country and a vet is a long way, so I would appreciate answers to help us take care of this abandoned dog.