I’m aware of how to do the calculations, but this house is just roughed in, without any appliances, no HVAC installed yet. It is ready for drywall. The service panel and meter base are physically attached to the house, but not wired. The main electrical distribution panel is in place, but no breakers installed. There is a separate subpanel for the pool equipment, but not marked as to the power rating there. I just happened to open the service panel, and saw that the main breaker is 150.
I realize 150 is sufficient for most applications, and well within code. My reason for asking is that at this stage, it should be very easy and cheap to change to 200 amp - most likely just switching out the main as Gerry said. If I wait until all is installed, it would be much more complicated, and unlikely to get the builder to easily go along.
And to answer, this house is all electric, with plans for high efficiency heat pump, dishwasher, all the appliances, plus a pool and separate spa. The pool will be heated with its own heat pump.
Without doing the calculations, with the timing, I thought I’d suggest (emphasize on suggest !) they upgrade it to 200 amp service.