You don’t need a top shelf shotgun, especially at 15. I outshot 90% of people I shot with from age 11 to 32 using an 870. Some of the parts are cheaper on the express, but it will last you 15 years until you can really afford something nice. Even then you might outshoot your new Beretta or Bennelli with The tried and true 870. Shotgun shooting is almost all technique and not nearly as much the gun.