Gota have an eye for those situations man. Don't always go the safe way not all people are out to screw you over sometimes they are cool as hell to you. You just need to be a better judge of people. Like if someones alll coming out with any sort of weapon when your buying or selling get the fuck out of there or mace them. Had a kid pull a knife on me once was after my pipe (just boughten) so i fiddled around in my pocket got the thing so the nozzle was face up. Extended my arm like i was going to give him my pipe and emptied the can on him. I dunno get a can of mace, you dont have to be complicit with that kind of bullshit.