Is disassembly acceptable when doing a deal? I've bought some dirty a** pistols, and never have done more than a quick look over/function check.
I wouldn't think it is unacceptable if you were buying something from me and you wanted to take the slide off and do a quick check, but admittedly I have never done that before. Sorry that happened OP, hopefully the member you traded with will be honorable and undo the deal.