Hi kevin301,
Cos the other 2 of my gf went Sydney and Perth before, that is why this trip we choose gold coast.
yeah, we also thinking to book our stay via airbnb. The only problem is not sure whether is safe as this trip will be all girls only.
I've only made use of AirBnB twice before (Kyoto and Bali) and both times turned out OK. 2/2 is a good start but not really conclusive.
Depending on which month you go, it may also be OK to book a serviced apartment. Try the usual booking sites like agoda, booking.com, wotif, etc. If price is similar to AirBnb, might as well just go with a regular hotel operator, no?
Personally I feel that Gold Coast is quite tough to get around by public transport. The city is pretty spread out and public transport isn't that great, though it is slowly improving.