4S dealership records are directly connected to the manufacturer's database, making the data hard to tamper with and the most reliable, with original parts guaranteed; third-party repair shops usually are not connected, making their data unverifiable. Therefore, we only consider the connected records from 4S dealerships as valid historical documentation.

RoRo ships usually charge based on the vehicle's volume (length x width x height, calculated in CBM) in tiers; container shipping has a fixed compartment price. We will calculate which method is the most economical for the current sailing.

We will directly check the registration certificate (the big green book) and count the number of changes.