I wanna start out with saying I do not regret having a composting toilet system , a septic system is destructive & i want no part of putting one on my land - I do however have some things to share with those who are considering a similar composting solution to mine.
(Not all composting toilet methods are created equal!! You can spend anywhere between $10 handmade to over $2,000 mega system.)***
#1: the urine container fills up fast. For just me alone it fills up in a week or so. If people come over, it has the chance of overflowing if I dont think to empty it right before they get here.... which i am here to say is GRROOOOSSSSSsssSSSS. So gross! JEzuz, and i dont get grossed out very easily, as ya'll should know. I can skin a dead chipmunk, but urine splashing out onto my face is another monster all together!*
#2: You will be scooping poop! The thing is it is supposed to be nice composted poop turned into garden goddess blackness, but there are times when this plan doesnt work out, and also what about the very last shit you took before you are about to clean out the poop container??? Yeah, that one didn't have time to compost. This is when i really think a Humanure system, handmade with a bucket that can be easily pulled out and dumped is MUCH better then any permanent system (if you are in a cabin, obviously not in a boat!)*
#3: Winter = Cold = Poop ain't gonna turn to dirt! My cabin was not warm enough to keep up composting temperatures, so basically what happened during winter was the poop was kept at a really nice cold temp that kept it fresh! mmmMmmMm! Perfectly preserved poop waiting for me to scoop out!
#4 : When ya scoop it out the container, if it didn't compost good enough your whole house will stink like poop but worse. Enough said there.*
#5: Who's gonna clean up after? I know this sounds minor but the reality of it is a bit different, I have to use plastic bags or something to cover my hands and arms to scoop out the poop (cause remember some of it wont be composted), then i use a shovel to scoop it, and then a bucket to poop the poop in. So once all these things have poop on them, you have to find a way to clean them. Spray a hose outside, of course.... and have poop splatter back onto your clothes when it flings off the bucket.
I have chose to let time take care of these things, in the rain. I leave the buckets, shovel out in the weather to clean it off.
NOTE :::: ALL of this is way more intense (I believe) if you have more then one person using the composting toilet... I am by myself, mostly dealing with my own waste. Decide how much you love your partner ahead of time and be prepared to dive your hands into their poop if you want this kind of system.
Again --- BUCKET! Easy to remove trays! something, anything.... is better then scooping! Find a composting system that makes the removal of the waste as simple as possible, because in a ideal world it's black dirt, in the real world someone took a shit yesterday and it didnt get a chance to become black gold.
My vote is to have two systems ideally. Depending on your situation of course, but if you are in a cabin (aka not in a boat, RV, or tiny house on wheels) use a easy bucket humanure style toilet, and build an outhouse for guests during parties.
At least.... that is what I am about to start building this summer.