TCO = on-road price + operating cost (fuel, maintenance, insurance, parking, loan interest) − resale value. This formula reflects the real money you 'spend' to use a car over a period.
The on-road price is list price + registration tax + plate fee + inspection + first-year insurance. Operating cost depends heavily on how you drive (city/highway split) and your annual km.
ViDrive runs the whole formula automatically from Vietnamese market data — you just pick the car, city, and km.