Hiya i have found from my experience of moving here ,migrant agents will help you a little but getting a job is pretty much down to you ,you can try various job sites the best being
www.alljobs.com.au ,this covers all areas of Oz.
Regarding the house sale it is hard to tie everything up at the same time ,i would suggest if your dead set on this get the house on the market now you can always rent or skive a spare room for a few nights like we did and lets face it the last thing you want is to be unable to commit,we moved here approx 5mth after the visa had been granted and it does depend alot on the house sale ,,its a stressful time but youll get there,if i can help with anything please ask
Cal x