I record everything I do in the owners handbook, its got 12 annual service pages. Owing to the low mileage covered i tend to use one page to cover 2 years maintenance, a short note of what was done, i.e engine oil and filter, date mileage, make/type of oil used. I tend to run coolant for 3 years and brake fluid change every 2 years (although I think the service conditions would safely allow longer). Gearbox and diff oil, when i feel inclined but I think Mazda quote something like 60K for gearbox, maybe longer and with decent Redline fully synthetics i think thats fine, you could probably run it for life although I'm not an advocate of"filled for life". I did a gearbox oil change on my wifes 2008 VW EOS we've had from new last year (12 years and 108K) and oil that i took out still had a nice colour and viscosity "looked good".
I think that using the owners handbook to record everything keeps it simple for future owners, I don't bother to record king pin greasing....its too often. I do keep reciepts but running several cars i tend to place one big order for consummibles.
