they're both "third party" CTP - compulsory third party. the other one is "Third Party Fire and Theft".
i was talking about both (id say ctp for greenslip as it removes the confusion)
CTP-covers damage to other persons
THIRD PARTY- covers damage to other's property (just car also have a fire and theft OPTION, which costs a little more)
considering your on your p's (as i am now, greens though). i did an online quote for THIRD PARTY FIRE and THEFT, and it turned out to be 565 for a 17k r33 series 2. no mods
for me, ctp greenslip is about 500 as well.
In NSW, a CTP greenslip is compulsory for vehicle registration, i guess its not compulsory in other states.
If you weigh up the pros and cons, having comprehensive insurance means that in 3 years time youd be able to buy another car already. however in the event where you do stuff up, then you have the added benefit of getting all your money back (if you add mods, and dont tell the insurance company, they WONT reimburse you, also your premium will go up). add to that a $2000 excess for a male under 25 driver with a performance car (this is all for just cars). and youll be paying $5000 a year if you make a claim.
your premium will also go up if you make a claim.