Airsoft GI Item shipped broken,poor return policy...read on.. walnut, California

My 14 year old son purchased an airsoft gun, rechargeable batteries and extra magazines for the gun he purchased totaling $349.00.  It came in the mail, he fired 3 shots & it broke, we called the company immediately.  They explained that they are NOT responsible for broken items but they would "repair" the back if we shipped it back to them (this is one hour after receiving the gun & shipping would be at our expense).  I spent a week arguing this insane policy considering we just paid over $300 for a broken item that they would not stand behind...finally talked them into a refund....with a 15% "restocking fee" (also ridiculous but I had no fight left in me).  Luckily for me, I paid for the item through PayPal & I did not trust this company as far as I could throw them.  I filed a complaint with Paypal which I quickly won.  I did the honest thing & asked for a refund of my money minus the restocking fee.  I received $269.00 from paypal back into my account.  I sent the gun & all of the accessories back to the company according to their strict labeling policy so they would not reject the return.  Never heard from them, honestly, I never thought about it again.  Today, I opened up a letter from a collection agency on behalf of Airsoft GI...they send my 14 year old son to collection for $369.00 + 89.00 in "fees"! THEY HAVE THE MERCHANDISE!  Do NOT buy anything from this company, I beg anyone who reads this....they are awful!