I think if you can poo in a bucket and deal with that you are on your way to living off-grid. My poo buckets which are two months old are filled with bugs eating away at it and it like 50% lighter. Bugs can really compost human manure real fast in an enclosed bucket. In the winter time i burn mine in the woodstove. I use newspaper to poo on in my portapotty and then toss it right into the fire. My portapotty is just a small camper toilet with a elder chair riser with handles. The riser lets me clean it and the portapotty lets me line it with a plastic bag with some holes punched thru for the pee to go into. I then use the pee with woodash and sawdust or woodscraps to compost my food scraps to be used for later to fertilize around fruit trees. I guess one doesn’t have to add the food scraps but i do since it sometimes has bones etc etc. The urine is a great nitrogen and the decomposting wood and ash with it makes for a great total fertilizer.
Yes dealing with this basic human element is the best way to start to learn to live off-grid because if your putting in a expensive septic system well your taxes will go up and if you even have a composting toilet and bathroom your taxes will go up but if your living in a no indoor plumbing building your taxes will stay low. Then you want to be sure you are dealing with this element properly. Master your poo and pee and you have taken the first step to going off-grid.