Work backward from the execution milestone for tire costs; a supplier's general response is only a lead. Identify who provides energy-use, maintenance, insurance, downtime, and residual-value data for the same duty-cycle period, who reviews them, when they expire, and who approves an alternative if there is a discrepancy. This identifies issues before a low purchase price masks energy use, downtime, and capital tied up. Retain ranges for items without local data and update them after trial operations.
See Can spare parts be ordered together with vehicles from China?.