No, I don’t know anything much about inverters.
You want to buy larger than just the watt number that you need, because of the start up drain from an appliance, for instance a refrigerator that draws 200 watts when cooling, may start itself with a 500 or 600 watt draw for a few seconds.
I think that it might be best to buy a pure sine wave inverter and it is what I am holding out for because it seems to be suitable for all electronics, whereas some inverters are not, and if you are going to buy one, it might as well be very versatile, besides, quality battery chargers for flashlights, might be sensitive to that.
With a good car battery, an inverter, and a $25.00 solar trickle charger for the car, a car battery can suffice for years worth of very light use, although the car is barely or never used, of course if there was no gas, then the battery and trickle charger would be brought in to the dwelling.