My late Dad who was audited alot used to make the guys come to our house, sit them in an exceedinly uncomfortable chair, make himself a bourben and branchwater and talk non stop telling stories, he was a great raconteur. He never offered them a drink, refused to let them use the bathroom saying it was out of order, drank his bourben, refilled it and had Mom keep the tv on in the next room blaring. He never paid a penalty, never had to make payments and the agents left usually after three hours. He didn’t organize anything and when they requested something would wander about the room searching through piles of recepts and interrupting only to refresh his bourben. He was a CPA himself and was amazingly good at his game.
Took the CPA exam myself, dated an IRS agent once for a while she was one of the nicest people you ever hope to meet. I almost married her! I think she was near the top of the Knoxville Tennessee office when she retire.