I came across this spear-fisherman and his brother at Scarborough busy trying to sell the last of the ten yellowtail that they'd speared close to Cape Point. Their price? R100 per fish! Isn't that just a crazy price? I'm not 100% sure what yellowtail costs in supermarkets, but I'm sure that it's in excess of R50 per kilogram, making this buy an absolute bargain.
The only reason I didn't buy one was that I'd have had to transport it 65 kilometres home in the back of my car, without a proper fish bag to contain the fishy aroma. :)
I wrote an article a while back about recreational fishing around the Cape Peninsula, so check that out for details on where to purchase permits - they're really cheap. I had a quick look for limits with respect to quotas for line fish like yellowtail and it appears as though it's currently limited to ten per person. So, if you're lucky enough to bag a whole lot of yellowtail, make sure that you only take ten - the fines are pretty hefty.