Ruby, That is far too much.
In fairness, you can't expect QB members, who are mainly in the USA, to comment on prices for second hand sewing machines in Australia. The market for sewing machines depends on where you are, but anyone putting a three figure price in any currency on a 99K is trying it on. The market for sewing machines varies depends on where you are.
I suggest you read all the advice on this site
http://www.helenhowes-sewingmachines.co.uk and if you want to try sending a message to the young chap who has this blog, he is in Australia and will give you a much better idea of what you can get and for how much there
http://scheong.wordpress.com/categor...wing-machines/ I've been in touch with him before now - he's very easy to get on with.