DETC, which accredits this school, is a well-established USDoEd-recognized accrediting body, but it is historically for “trade” or technical schools: only very recently has it branched into institutions giving “academic” degrees (or rather, the trade schools have expanded themselves into college format).
What is normally called “accreditation” in US Higher Education is what you get with one of the mentioned Regional Consortia of colleges, that preexist the DoEd list and are recognized for “academic” schools, even for the distance-ed programs.
A DETC-accredited school is a real school where people do actual working and learning, BUT as ftg has indicated, a baccalaureate under DETC will likely be considered at best second-rate specially if he ever wants to apply to a Graduate School, or transfer credits to a regular college. (OTOH, I would hire a graduate of one of the longer-established DETC programs if he had the skills for the work I specifically want; just that I’d make sure he is aware he may be hobbled advancement-wise by difficulty in going for an advanced degree)
Refer him to this site, where they have some info on the subject: www.back2college.com/library/dist.htm
Normally I’d prefer to refer this sort of subject to the distance-ed boards at www.degreeinfo.com but there seems to be a problem with the site currently.
As to the cost, IF the $20,000 is for the whole usual 120+ semester-hour BA/BS course, it’s high but within the range of a sample I got from the schools in the DTEC site. For example, a school that charged you $150/semester-hour would add up to $18K in tuition alone for 120SHs.
HOWEVER if your friend could find himself a distance-ed program from a state-run college in his state-of-residence, he would likely get a bargain in the tuition rates, and regular recognized-by-all Regional Accreditation to boot. So do encourage him to look into that if at all possible (For example, Kansas’ Fort Hayes State U charges $122/SH for their Virtual-College Undergrads whether resident or not. No CompSci distance degree, though).