Cost of living in Melbourne

Hi everyone, my husband is considering taking a job in Melbourne. We are currently from NZ, where we both teach. The job is not teaching, but a field he loves, and a great opportunity. The employer has asked us to identify our salary expectations. We have visited Melbourne before, but have no idea on how much it would cost to live there. I may be able to teach, but we also have 2 children, so it will take a while to settle them. So my question is, what would be a reasonable salary to support 4 people on to live comfortably? We don't want to trade our pretty good life here to really struggle, but we also don't expect to be rich. We would need to pay rent, schooling, cars, food, electricity, all the usual stuff.
Thanks in advance!