Discounts (multi-plan, anti-theft, accident free, etc.)
Property Damage Coverage (i.e., 25/50/25...100/300/100...etc.)
Medical (total coverage)
Uninsured motorist coverage (i.e., 25/50...100/250...etc.)
Needless to say, "Full Coverage" using 25/50/25, no medical (not required for 'full coverage'), and 25/50 uninsured motorist would be substantially different from 100/300/100, 50K of medical, zero deductible comp and collision, 100/250 uninsured.
Of course, some folks with 'full coverage' don't even know what their coverage figures actually are...