Newb advice: order of operations - Accumulate credits then enroll vs opposite?

[mbcummings]

I'm pretty well decided on either TESU or Excelsior. 

Goal is fast track bachelors in liberal studies. I'd like a BS in psych but fastest track = best track and thus far lib studies looks faster. Maybe psych masters after.

Question: which will save more cost overall?:

1. Enroll and admit in one of the above first, then start taking courses from study/sophia (3rd party ed. platforms) etc. to aggregate.
   
2. Just start taking courses, then enroll and admit to transfer in/aggregate when all but "residency" required course/credits are completed.
   

Is this even a good or common question? (I've searched this forum of course, not to find answers.)
What is a better question and decision to make at this point, for how to save money (first) and time (second)?


FYI - personal context: old life-long student, non-combat vet with misc. college credits, a "diploma" from a private (and closed) trade school, and decades of professional experience in software design/IT. An ADHD diagnosis later in life explained a lot about my complex history with educational institutions generally. Trying to make the most of things is all.