When a project scales from one DC fast charger to several, the challenge stops being just "which charger to buy" and becomes "how much electrical power do I need to contract, and how do I distribute it" — and that's where many projects end up costing more if they aren't planned properly from the start.
The first step is understanding that chargers will rarely all run at full power simultaneously. A load management system can dynamically distribute available power among the chargers active at any given moment, avoiding the need to contract the sum of every unit's maximum power rating.
The second step is checking whether the building's or facility's current contracted power is sufficient, or whether the supply needs to be increased with the utility company — a process that can add months to the project timeline and should be anticipated as early as possible.
The third step is planning for future growth: sizing the service entrance and electrical panel to accommodate additional chargers down the line is usually far cheaper during the initial build than expanding it later, once everything is already installed and running.