for what you're planning, your nominal reserve capacity on the batteries should meet the nominal power draw for 3 days with no solar support.
your solar system should then provide not less than 50% of the reserve capacity of the batteries.
get 2 inverters, a small one for small loads and a larger one for larger loads, the small ones have less standby power draw and the larger ones are more efficient when loaded with something near the limit of the smaller one. it also gives you some redundancy.
With you're current setup you're good for about a day and a half.
(all on back of the napkin maths against how I would normally setup a similar system that did not have the ability to be externally charged by a vehicle, genny or other charging means.)
if you've got access to running water its surprisingly easy to pinch 100w or so out of the stream.
