there have been instances where the batfe has looked into individuals for excessive buying/selling/trading that I have seen on other forums. usually comes from either someone calling in a tip or agents browse forums like these looking for suspicious activity.
if you have any class 3 weapons, remember the batfe can visit you anytime they want to and look for whatever they would like
Nope, the scope of the search is limited to the weapon(s). Once those are produced the search is over without a warrant.
Or your consent... Unless you leave incriminating stuff laying around in plain site, LOL