I changed to Jepps recently because of my employers requirements, the charts are different, but once you get used to the nuances, they really are the ducks nuts.
The price will change with the exchange rate, but I think you'll find for the basic package, which is the Australia Domestic Route Manual (includes high and low charts, approach charts, aip's, etc) is around about $550. That includes the one year amendment. If I remember correctly, the jepps are more expensive initially, but after the first or second year they work out much cheaper.
Just as a side note, I seem to recall ASA a while ago saying that they are going to start charging for their information, which would mean Jepps will go up in price. Anyway, good product...