future proof sizing of a subpanel
We'll be replacing the upstairs fusebox subpanel and the wiring to it. Currently there are only three circuits, but the upstairs has no HVAC and will likely get it at some point in the future. Not to mention a possible need for new circuits at some point.
It is barely possible that we might want to put a small water heater upstairs - possible but unlikely. Other than that, and a future HVAC system, we are only serving 4 bedrooms and a bath.
I want to do this panel upgrade once and be done with it, but what should I go with?