13 inches of thick virgin hair

I have long naturally wavy to slightly curly hair with quite a lot of auburn undertones. I’m Scottish if that helps. In its natural state my ponytail is around 3 inches. I wash three times a week and only put heat on it once a week . The rest of the time I leave it natural. I trim it every 4 months. Don’t smoke. Don’t drink and don’t eat processed food.