Easy Peasy | PHP Script Question | Guidance

Hello fellas,

Is there anyone that can tell the disadvantage of using a script that you buy from codecayon or coderster ETC ?

what would be the good advice I would have to know before doing so ? Tell me what come to your mind or on the top of your head

I watched couple of video on youtube showing how to install and upload the PHP script to your server or in CPanel, but they don't tell you the headache a newbie will have after doing so.

Thanks,