Help a beginner please! Big 3 questions

[Mira]

Hello everyone,

I just stumbled upon the world of credit-by-examination today and was quite intrigued. However, I had a couple of questions that I would very much appreciate those of you who are more experienced answering.

So, I wanted to ask which one out of the big 3 allows you to earn the most credit by examination? Also, assuming max credit was earned by outside examinations, how much does the university itself cost? Also, what other requirements do they have so I heard COSC requires a lab experience? 
Basically, overall, what would be the most suitable, cheapest, quickest  option for an international student who prefers self-studying?
Also, how do you meet the individual requirements for the degree. I checked TESU's website for a couple of degrees but it seemed a bit vague. How do I know what examinations would be required? Is it also possible to graduate with two degrees if you meet the requirements for both and would you have to pay more for that?

Sorry, they are a lot of questions but I would very much appreciate you answering them. Thank you very much!