Trace what you can, apply overhead using the chosen base, then check the price.
The arithmetic
Overhead applied to a job rate × ACTUAL quantity of the base used on that job Rate is budgeted; the quantity multiplied by it is actual Total job cost direct materials + direct labour + overhead applied All figures GST-exclusive Price total job cost × (1 + mark-up %) Mark-up must cover profit AND any unrecovered overhead; GST is added when invoicing the customer