Depending on your definition of "decent"(unless you are a complete snob) you could get some really good older cars for that price. Start at the usual place cars.co.za, gumtree, webuycars....
Most of the dealerships in my area are snakes and ridiculous prices for secondhand vehicles, ended up asking my local mechanic and got a Hyundai Accent 1.6 2006 model with 37 000 km's for 60K.