Also, a 600W Inverter is very lightweight. It is unlikely it will handle the starting current requirements of a standard domestic Fridge/Freezer.

I actually calculated the peak power requirements of a farmhouse I bought last year (just to see how self-sufficient I can make it)... including the swimming pool that I've had put in... 15kW - and that's even after considering it has about 60% LED lighting throughout the building!