Well, my BMWs (F13, F15 and G12) have full warranty and free parts/oil changes/wear & tear (including disc brakes, pumps, filters even windshield wipers etc, excluding only tyres) for 3 years, so maintenance costs are zero. I hardly keep cars longer than 3 or max 4 years, so no major costs incurred for my modest fleet so far. The incoming W222 has $5000 rebates in service vouchers, so that should last at least a year or two... Fingers crossed haha