Concerns about over-stressing the electricty supply at some future date are not a reason for refusing one vehicle today. They are a reason for doing what you set out to do – have a plan for the future.
I would suggest that concern for exceeding the electricity supply for the building is not entirely unreasonable and care should be taken so that the first X% don’t take up the available capacity leaving the remaining 100-X% in difficulty. A common misconception among about-to-be EV owners is that they need more than an ordinary power point. Vendors of EVs often encourage charging installations of 32A or even suggest that 3-phase at 32A is needed. This is nonsense. I have been charging adequately on an ordinary 10A outlet for over a decade and it is sufficient. As car battery capacities get larger, the need for faster charging is lessened, not increased, because a half-full battery will still have more than enough range for local trips. Perhaps be a bit generous and allow a 15A outlet but I wouldn’t give more without being sure the building can handle the extra load of X units times 15A at peak time.
This is being a bit cautious because people would hopefully respond to retail tariffs that encourage avoidance of the evening peak through time of use or peak demand tariffs. Not everybody will be charging at once but the Australian Standard have this assumption included unreasonably for peak demand calculations.
My Hyundai Kona electric has over 400km of range so I routinely have it set to stop charging at 80% for better battery life and I only charge to 100% if planning a longer trip out of town the next day. I plug in every few days when it goes under 50% and rarely let it run low. An ordinary 10A power point adds almost 200km of range overnight. A 15A outlet, almost 300km. So, don’t let the early adopters gobble up the excessive capacity they might think they need.
If it is practical, re distance to meters etc., it is preferable to have charging points wired back to the individual units’ meters. It saves the OC having to find an equitable way to meter and share a common property supply. Supply from the common property can be done in various different ways according to circumstances but best avoided if possible to go back to the existing individual unit meters.
I could go on with plenty more detail but that is enough for now. Anyone wanting to talk through more detail is welcome to send a message via this site.