Dog DNA testing has anyone tried it?

I have been very curious to try one of these Dog DNA tests on both my dogs. Just out of curiosity and for fun. I have my ideas on what my dogs maybe but would really love to see if the test matches what we think they are. Has anyone used one of these tests and were the results what you expected or even remotely accurate?

Any companies that do DNA Ancestry tests?

I want to learn about where my ancestors came from by a DNA test because of some issues with my maternal grandparents origiins.

Are there any such DNA tests at all?
A link would be great, if you have experience with such companies i would like to hear about it if you dont mind.

In medical school do you ever do DNA testing?

I ask this question because it relates to a story I'm writing. My main character is a medical student and needs to have her DNA tested on her blood and her hair or saliva.

In medical school, would you ever do DNA tests and would you ever use your own DNA, specifically ones own DNA?

Has anyone ever used an at home DNA paternity test?

Wondering if anyone has ever used one of those at home, private DNA tests and, if so, how sure were you of the accuracy of the test? How long did it take you to get the results?

How much to dog DNA tests typically cost?

I heard that dog DNA tests are now available so people know what kind of dog they have. Have any of you ever had one done on your dog? On average, how much do they cost????