First off, Tim I just clicked over to your YouTube channel and I love what you guys are doing. Great job doing life together as a family.
We are a family of six starting a homestead on 16.5 acres in Central Kentucky. We are also planning on using a composting toilet. I think that we will eventually use a SunMar unit (maybe) or a similar design (we're permitting our timber-frame and straw bale house, so we've got to work with inspectors who won't issue a certificate of occupancy with just the humanure bucket system. But, right now we use a simple bucket system when we are camping on our property. I'm a teacher (for now) so we have summers off to work on our land, so this is our only toilet when we live in the camper for two months, and it works fine. I'm attaching a few pictures of what we have now, and I'll describe the rest and try to post some pics again later when I can get through the snow-pack to our place. These pics are in our summer bathhouse which has a loo on one side and a shower on the other.
This is the bucket loo in the bath-house before we put the skin on. The water is gravity fed from rain catchment up slope, there is a homemade urine diversion unit underneath that seat which separates our solids from the liquids. The urine diverter is flushed by the sink water, and it simply empties into a mulch pit down grade at the base of a big cedar tree. The solids are then composted. Here's closer look at the toilet itself when it was just surrounded by a tarp on a clothesline in the woods.
The wood is just scrap that I salvaged. The top piece had a big map painted on it. (sorry no inside photos, but I can arrange that if you like). The two black pipe elbows you can see are air intakes that allow air into the chamber, and what you can't see is the tall black chimney that rises out the back to vent air out. Not as important in the woods, but I'm experimenting for the future. That "tank" on the back of the toilet is for our carbon (sawdust, coffee hulls, shredded barley straw, etc.) We put in a scoop each time we poop and and it works to break down when the bucket is emptied into the compost bin. Right now ours only gets seasonal use by the family. I hope this helps. Good luck on the homestead.