The key number is the amount of Rand per students that graduates.
Unisa's total income in 2018 was R7.4bn (fees and subsidies)
The amount of graduates they produced in that year was 52318.
Which is about R142k per graduating student per year.
https://www.unisa.ac.za/static/corporate_web/Content/News & Media/Publications/Annual reports/docs/unisa-annual-rpt2018.pdf
Stellenbosch on the other hand produced 8 899 graduates at the cost of R5.413bn.
Which amounts to about to R608k per graduating student per year.
http://www.sun.ac.za/english/Documents/Annual Integrated Report/2018/2018_SU_Annual Report_English.pdf
This is for total income, if we just looked at government income:
Unisa gets R3.6bn, whilst Stellenbosch gets about R2.023bn.
Which then means that the cost to the government per graduating student is about R70k per student for UNISA, whereas it is R220k per student at Stellenbosch.
These numbers should easily show you why UNISA is a better investment for education than almost any other
adult day care centre university.