Melbourne to the Valley (Silicon Valley)

Hi Everyone,

I am currently interviewing for a company in the Valley, and seriously looking to move my family from Melbourne Australia to Silicon Valley (company is in Palo Alto). Family consists of Mum/Dad and 3 boys aged 11,8,1.5

The main concern for us is the Salary/Package.
How do we compare an Aust Salary to one in the Valley?
What is enough for a family?
Where do we start...?
Any families that made this move from Australia?
Medical package/insurance any standard around this?

Thank you!