Hi there, I have not been on the forum for a while, and have only just seen all your questions about Perth. We have been here since Feb also on a 457 visa, and also not buying until we have our PR sorted out.(hopefully soon) we have, however, looked at various suburbs and houses to give us an idea. At the moment we are staying in Duncraig, which is 5 mins to the beach, however, my partner has to commute into the city every day, and does not enjoy the commute that much. When we decide to buy, we will either buy closer to the city, or near to the beach. I think we will end up buying a property close to the beach and in the northern suburbs. As far as crime goes, well I am from South Africa, and as yet, I am still in the "honeymoon" phase. We have not had any bad experiences since been here, but a friend of ours had their car "egged" the other night, while parked outside someones house that they had gone to for a bbq, but that has been the sum total of "crime" that we have experienced. As for bringng up children here, what a wonderful place, could not be better I reckon. I do not have children, but there are parks everywhere, and if you live close to the beach, there are parks on the beach for them. There are pathways on the pavements for peoople to walk along and just in general, I really do believe that it is a great place to bring up children.
Back to the suburbs, I think North of the river is best, especially if you have children, and you can get really good houses in newish areas like Clarkson, Landsale etc. Very good deals, and the standard house here, is 3/4 bedrooms, 2 bathrooms, media room, theatre room, lounge kitchen, double garage, laundry, open plan lounge/kitchen.
Good luck and hope that Perth is as kind to you as it has been to us.