Capt. Curl, "reporting income" should include the fact that the seller thinks he made a profit, am I OK so far? If the Service will accept a statement of profit, shouldn't they also accept a statement of expenses and initial cost? Should I include the profit from a lawn tractor that I sold in front of my house at a price higher than I paid for it? I think the original poster is asking whether anyone from the Service will come after us under present law if we sell a bunch of guns at an auction house. Now we know you are an attorney and may decide not to reply, but I hope you do.