I'd say you're overthinking this a bit.
While it's important to communicate your limmits and wants to all of your partners, I don't think such details should be defined even before any other relationship actually starts. There's a long way between deciding to go poly and have someone move in with you, and every person is different about sharring stuff, or bathroom rules.
You just read a lot about how to manage jaleousy, to be secure of yourselves and keep communicating a lot.
Meet people without such specific rules and expectations, then go adjusting and talking things over as the relationship evolves.
Me, female in a V with Peaches, live in boyfriend and CC, boyfriend.