I’m purchasing a property which will not perc for a conventional septic system. There are alternative septic systems that are possible, but also I’m wondering, what about an alternative system altogether? Does anyone have experience with handling greywater and waste separately (say composting for waste) in a home with several members?
Are you trying to be permitted by the county/local gov?
It’s definitely possible to do graywater separate and compost human waste. I’ve done composting in the past and it can work great. But getting the county (I’m from the US) to sign off on it is really depends on your local government.
One great resource in general is the The Humanure Handbook By Joseph Jenkins
It massively depends on your local code enforcement officer. If they are a dick, don’t buy the property. If you haven’t met them yet, you will. You didn’t say where you are, so ymmv. If you’re in Maine, I dug my own, town approved primitive wastewater disposal, and could help.