Aluminium is what separates a used G30 panel from a new one. BMW made the doors, bonnet and parts of the suspension from it, and aluminium cannot be pulled straight the way steel can. A distorted member is scrap rather than a repair, so on this model a panel's history counts for more than it did on the cars before it.
The 2020 facelift was a bigger change than photographs suggest: different headlights, different rear lights, revised aprons, a larger grille. For lamps and bumpers that is the line, and there is no arguing with it.
One expensive mistake concerns the plug-in hybrids. A 530e has a charge socket in the left front wing where a combustion car has nothing at all. Two wings in the same colour are therefore not automatically the same part.
Our stock for this model is mostly lamps at both ends plus doors and aprons — which is to say the things a rear-end shunt destroys first and leaves usable afterwards.