As much I think your intentions were good, I think you're jumping the gun.
I had some preconceived notions about how much cars cost and what it takes to get financing. I did the research because I was curious. She did not ask for my help and I have no intention of offering any information unless she brings up the subject. I also won't recommend a particular car and I'd insist she visit a mechanic before purchasing. I did the research and asked questions simply so that I'll be better informed. I had extra time and I wanted to do it. I'm sure she's done her own research as well. It's not something we talk about at the moment. I was just curious what others, who have more experience than I, thought about the situation and what she might be able to afford.
I think you were pretty quick to get on your high horse there. I never said she asked me to do the work for her. I did it on my own because I wanted to, because I care, nothing more. I wanted to be able to offer some information (not necessarily advice) if she ever wanted it. I happen to think friends go out of their way to help friends. If she never asks, that's fine. I still learned something. Maybe I'll want to buy a new-to-me car one day.
Sometimes you can let people make mistakes, but if you have the chance to offer some help when they truly need it and are willing to accept it, then isn't that what being a friend is about? I'd rather try to help and lose a friend then have her end up unemployed for years because I wanted her to make her own mistakes. There is plenty of time for her to do that as well

I'm still not offering the advice. I'm waiting until she brings up the subject.
Thanks to everyone who offered advice. I feel as though I've learned a lot. I hope things work out for my friend and even if I never share my new found knowledge with her, I still think I've gained something.