We only have one because we need two cars, my wife is disabled and so gets a much cheaper lease, and the other car is petrol and so can do just the odd local journey, infrequent long journeys and towing. Leaving the electric car for almost all journeys.
The supply cable may be fine. Mine was a 60A fused supply, but as soon as I upgraded from a fusebox to a modern consumer unit, the supplier uprated the main fuse to 100A - there was no need for a supply cable upgrade.