For any jobs that are 5kW (inverter and panels) or above they require a VRC.

For any jobs that are 4.75kW panels or less no VRC is required.

For any jobs that have a 3phase meter box, will require a 3 phase inverter to be installed (or potentially 2 or 3 single phase inverters connected to each phase-grid approval determined).

For any jobs 5kW or more that on single phase, will require a single phase inverter and panels reduced to 4.75kW.

The 3 phase rule only applies to systems 5kw and bigger anything 4.9 kw or smaller can be a single phase inverter no matter wether there is 3 phase or single phase.