someone i know went through this back in the early 90's,he was full time fishing and was making good money after expenses, he did as his tax person said, thought he had everything he needed.they found almost a hundred thousand they wanted to get him for i don't know what they setteld on but they dig up anything and everything they can,not just fishing they had his finacial record for the max years they can go back,farming expenses and all,so unless you are making a lot of money and have your FISH in a school it isn't worth it,i do keep milage,and gas until tax time my tax person said to keep the expenses with each tournament and write those off only,last year i had to show close to 1700 and with miles and gas and room at ky lake they figured 750 expenses for that tournament.but overall it didn't make a big difference either way.