I do it as the year goes by with the rentals in binders so its all organized. I use hrblock online every year so it rolls most of my data automatically.
Right, but the time spent during the year is still time spent. Then there is stuff like, oh, say I bought a couple cases of oil on sale, and used some in vehicle A at 42 % business usage (plus the logging & figuring of % business usage!) and some in Vehicle B at 29% business use. So to be accurate I gotta track how much oil I used in A and how much in B. I looked some years at using the std. mileage rate, but usually did worse with that — and one still has to log miles, etc. I probably ought to have Wifey also create a better spreadsheet for vehicle expenses, and try to keep up with it better, but I’m just so damn backlogged with bills & accounting & paperwork all the time anyway — and this is just for a silly little 1-person business.
Where’s that cartoon about computers “reducing” paperwork...?