+sub discount_from_source { }
+
+sub best_price {
+ my ($self, %params) = @_;
+
+ return () unless $self->record->is_sales;
+
+ my @prices = $self->available_prices;
+ my $customer = $self->record->customer;
+
+ return () if !$customer || !$customer->klass;
+
+ my $best_price = first { $_->spec == $customer->klass } @prices;
+
+ return $best_price || ();
+}
+
+sub best_discount { }
+