After graduating high-school, I did not attend a university and instead decided to enter the work force. Eight years hence, I would like to pursue a university degree but I am not entirely sure which credentials are important for an adult freshman. Are my high-school transcripts still relevant almost a decade after the fact? Do universities consider professional experience in their admissions process (I have 6 years professional experience related to my intended field of study)? Do I have a shot at competitive university even though my academic history is essentially nothing? With sufficient review, I expect I can achieve high standardized testing scores, but I wonder if that will be enough to compensate for such a huge gap in my academic career.
The crux of my question is: how should an adult freshmen prepare before applying to a competitive university?
Ask the university.
I went to college for one year after high school, then enrolled in a different university several years later (which I completed; both in the U.S.). My second university used my high school transcript and test scores from when I was in high school (I had to pay an extra fee to retrieve my old scores), as well as my transcript from my previous year of college (even though only one class actually counted for anything). They did not consider any professional experience.