CTP is a eastern state third party cover that is seperate of rego, In SA it is automatically factored into registration costs, but that only covers third party bodily injury. A three monthly rego on my 180sx costs $165 for three months and gets cheeper if you bulk buy.
You'd be a clown if you took a pocket missile on the road without any third party property cover. In SA i have a 6cyl falcon insured for tpo cover for about $122 a year. I think WA is fairly similar to SA with QLD and NSW being some of the heeftier of the charges due to simple risk averages - if you want cheep insurance move to Tasmania - The cheepest state to insure anything!! Double the amount of eyes means less accidents - lol

Check out "Just Car Insurance" if you are young as I refer drivers that the company I work for won't insure to these guys. ph: 13 1326 they take on imported vehicles and younger drivers.