How to create "personnal" shipments ?

Hi everyone! I have a little problem on my DarkRp server: How can i make shipments that set it's owner for the first player that takes it? Example: i have the Rprotect camera and terminal, that only the owner of the entities can link and configure, the problem is that when the hardware seller sells it, the camera and scanner belongs to him, so the buyer can't use them. It's the same for the weapons locker , only the seller can open an close them :/ So if anyone knows how to make that it would be great :P Thanks!