Katie is a nurse so her income will fluctuate. Most recent 2 payslips and FY14 group cert will likely be required given recent changes to regulations.
For good measure, 2 x payslips less than 60 days old (both) FY14 group cert and ITR and 3 months statements for any lending products you have with other institutions will probably cover most banks policy.
If the deposit is cash from under the mattress (i.e. not in a savings account) you might need to verify it.... feel free to pm me if needed
Can't see the bank caring about the cars though.