At UCT: Deans Merit List (above 70% aggregate) gets you a cool R9k. There is a limit to the number of top students that can get the funding though. So aim higher. Bursaries may be hard to get in the first year, but there are many opportunities further on.
Most bursaries cover the cost of accommodation too, so don't stress.
When applying for the national loans being white does not have an effect, I got one (UKZN). Also try transnet, know a few engineering friends who have from them.