[mothered]

Weight permitted, you can use the missing Item method.

• If I say the package was missing: I should before perform a "test run" to see if they have a CCTV system.
  
• If I say the inside of the package was missing: I could do it but in that sense I may be forced to send the package back (without the item of course), but losing the possibility to sell the item since I don't have anymore its original box.
  
• If I box the item sending back something else: I can keep the package + the item, without caring whether or not the company which sold me the item had a CCTV system.
  

Am I wrong?

@mothered
Does it make difference where I order it (product or this seller)?
The rows I wrote above should holds for both of them, right?

It will be packaged In the exact same manner, so It doesn't matter where It's purchased.