The companies selling these products like to imply that you will be able to power your whole house with their systems. Guess what, they can't. Because most US panels use split phase to break the 240V incoming into 120V circuits, you only get your plug-in solar feeding half the breakers in your panel.
Now, in order to do plug-in solar properly, you should have a dedicated plug for the inverter. While you have the electrician there, have them arrange the breakers on your panel so your large draws (AC, washing machine, etc) are on the same leg as your dedicated solar plug.