If you live in Cape Town you can go to Cape Gold Coin exchange http://www.krugerrandsa.co.za/ You can also leave the coins there and trade them as you go along. The web site tells you the buy and sell prices everyday and I think you can trade them online.
History. Bull markets have 3 distinct phases and if you look and average them out thats the kind of life span then "generally" have. Sure they can be longer and shorter but hence the average. Im using history as my guide. Government stupidity is helping the gold bull too :)