Updates to Product Model, product updates, enable pricing update, improved formating of product services

app/Models/Product/Broadband.php

@@ -6,6 +6,7 @@ use Illuminate\Support\Collection;
 use Leenooks\Traits\ScopeActive;
 
 use App\Interfaces\ProductItem;
+use App\Models\Invoice;
 use App\Models\Service\Broadband as ServiceBroadband;
 use App\Models\Supplier\Broadband as SupplierBroadband;
 
@@ -34,6 +35,8 @@ final class Broadband extends Type implements ProductItem
 	// The model that is referenced when this product is ordered
 	protected string $order_model = ServiceBroadband::class;
 
+	// When comparing billing/pricing/charging, what metric to normalise to
+	const DefaultBill = Invoice::BILL_MONTHLY;
 	// The model that the supplier supplies
 	const SupplierModel = SupplierBroadband::class;