I've been shopping for about five years, but my first three years I was strictly with MSI & Marketforce. I had no idea so many others existed so when I started shopping full time last year, taxes began to feel a bit overwhelming, even with great records and all the advice here for spreadsheets and such.
This year, I feel just little to no anxiety about it. I have my mileage book, my maps, all my print outs, everything is organized by date and reconciled digitally and by hand. I have digital copies and hard copies of all shops and such. I just feel so much less stress about it this year than previous years. Of course, there is the matter of one company not helping me make sure I have a copy of records... we moved twice and that one file has wandered off into space... just the actual prints of locations... but I'm seriously not even stressing that.