One issue that I detest is that if you operate from your home - it is looked at by the BATF as a Business that they can inspect at any time they desire. They can search your home, open your personal gun safes and inspect every firearm in them, to determine if any are listed anywhere as lost, stolen etc..
I certainly don't purchase any firearm I believe would fit any illegal criteria. However many in my collection are quite old (some 100+ years) and obviously some may have been reported lost or stolen 40 ~ 50 years ago!