Optimising Supplier Layout and source code placement

app/Models/Cost.php

@@ -15,6 +15,12 @@ class Cost extends Model
 		'billed_at',
 	];
 
+	protected $with = [
+		'broadbands',
+		'generics',
+		'phones',
+	];
+
 	/* RELATIONS */
 
 	public function broadbands()
@@ -37,4 +43,24 @@ class Cost extends Model
 
 	/* ATTRIBUTES */
 
+	public function getTotalBroadbandAttribute(): float
+	{
+		return $this->broadbands->sum('base')+$this->broadbands->sum('excess');
+	}
+
+	public function getTotalGenericAttribute(): float
+	{
+		return $this->generics->sum('base')+$this->generics->sum('excess');
+	}
+
+	public function getTotalPhoneAttribute(): float
+	{
+		return $this->phones->sum('base')+$this->phones->sum('excess');
+	}
+
+	public function getTotalAttribute(): float
+	{
+
+		return $this->getTotalBroadbandAttribute()+$this->getTotalGenericAttribute()+$this->getTotalPhoneAttribute();
+	}
 }