Before layout is locked
Confirm servicing availability, flood context, geotechnical classification and the legal discharge point. Each of these can invalidate a lot layout after it is drawn.
Before lodgement
Check that road grades, intersection sight distance, driveway crossings, drainage levels, earthworks balance and utility trail alignment are all mutually consistent across the drawing set.
A set that contradicts itself will be returned regardless of how good the individual sheets are.