I wonder how many of us would keel over if we actually lined up every receipt for our vehicles; purchase price, mods and all, and then added them up...
I track every single repair I do and every part I purchase for my Rovers, including tools. I do not track expenses like fuel, windshield wiper fluid, public lands permits, parking, or other minor incidentals. Everything from fluid changes on up goes into a large spreadsheet showing date and odometer reading. If I could claim a deduction on my tax return for all the money I spend on stuff from Tillery...I could buy even more parts.