Here is the web page where I hired the bike from, with costs.
the also have a shop in Perth that deals Kawasaki
The rental includes insurance (less a deductable, called excess in the even of a claim), so it is comparable, maybe even cheaper, than renting a bike in Canada.
Fuel is about $2 US a liter
B&B are 25 to 45 pounds per person per night away from major centers. Food pubs and resturants is 1.5 to 2 time the cost in north america, alchol is about par.