Do not use this agency - they don't follow their own contract terms, take your money without permission and don't even have the common courtesy to respond to your queries once they've stolen your money.
We were on a family holiday on the GC in Dec/Jan 2015 and it seems that while parked at a shopping centre, someone bumped into and dinged the front number plate. We noticed the damage upon returning the car and took photos and alerted Amil (Dave's father who seems to run the company) straight away. He held on to our $5000 deposit for almost 10 weeks without making any attempt to contact us - even though we tried several times to contact him about our money and the fact that we were unable to use our credit card for as long as he didn't release the funds. They just didn't care, and when he finally got in touch with us, he took almost $2000 from the credit card without sending us paperwork to review and sign off as permission to take the money. According to their own contract, they are supposed to send us a Schedule of Cost, which we review, sign and return to them before they take the money. This paperwork never arrived and we woke up one morning to find our money taken without permission. This is theft and despite us trying for over a month to contact him, he fobbed us off by saying that the paperwork was in 'the mail' - and then refused to take our calls or return our messages.
These guys are crooks - given the other reviews I've now read about them I wouldn't be surprised if they used their tracking device to locate and deliberately damage the car. Spend a bit more and go somewhere reputable - it'll save you a big headache.