On your inverter, as others have said 500 should work for most needs, if you want a cushion, go to 750.
On the solar, since you are in a C I'll presume with a genny, you can readily bump up your batteries with an hour on the genny, but to top off the batteries takes hours, which is what the solar does best. If you already have one panel look into its size and the controllers info. One beautiful thing about solar is that you can add to it. If your controller can handle 20 amps, you can add just another 100 watt panel and not have to change anything else. Later if you need more, consider future upgrades as well and when you buy controllers, wiring etc, leave yourself some flexibility.
Nobody can flatly tell you what you need, unless you want to buy the biggest system possible.
It will take you monitoring your usage a few times to get comfortable with matching needs to equipment and methods.
